Even with team rosters finally coming into focus with Opening Day approaching, there are still significant questions to be answered for every Major League team.

Whether it's a club looking to snap a lengthy postseason drought or the reigning champion Dodgers, every team has at least one lingering matter that will play out over the course of the 2021 season. With that in mind, MLB.com's beat reporters tackled the greatest unknown for all 30 clubs.

Here's what they had to say:

AMERICAN LEAGUE EAST

BLUE JAYS: The rotation behind Hyun Jin Ryu
Ryu is as reliable as they come, but the No. 2 through No. 5 spots in the Blue Jays' rotation remain a question mark. Left-handers Robbie Ray and Steven Matz have looked very sharp in Spring Training, but can they sustain that across a full season? And how many innings can we reasonably expect from them after a shortened 2020 campaign?

Toronto will likely open with Tanner Roark and Ross Stripling on the back end, given the injuries to the club's No. 1 prospect Nate Pearson and Thomas Hatch. They’re “starters," but that term will take on a different meaning this season as teams lean on piggyback strategies or multi-inning bullpen arms to get through a full 162-game schedule. A realistic goal for this group is simply to keep the Blue Jays in ballgames. Given the talent of this lineup, as long as the rotation can keep things close, there will always be a chance. The club’s depth is being tested already, though, and Toronto will need to win some of those 2-1 and 3-2 games along the way. -- Keegan Matheson

ORIOLES: What the pitching will look like
The Orioles, like all clubs, will have hundreds more innings to cover this year after the shortened 2020 season. But what the O's have more than most clubs is younger pitchers, all coming off career-low workloads, whose health will take priority over the club’s on-field goals in '21. The rebuilding Orioles simply aren’t going to push their prospects beyond reason. So how do the innings get covered? That’s the unknown. The O’s are brainstorming a variety of non-traditional pitching strategies, from six-man rotations to piggybacking to openers, and more. It’ll likely be a patchwork effort, with swingmen types like Bruce Zimmermann, Thomas Eshelman and others playing key roles to provide innings in bulk. These days on the mound, depth is always paramount. In '21, it will be even more so. -- Joe Trezza

RAYS: How will they use their starting pitchers?
The Rays will not be immune to the industry-wide uncertainty regarding how pitchers will handle the transition from a 60-game schedule back to a 162-game season. To start the year, Tampa Bay is relying on few sure things on a starting staff now without Charlie Morton and Blake Snell. Tyler Glasnow and Ryan Yarbrough are still here, and they will be joined by bounce-back candidates Michael Wacha, Rich Hill and Chris Archer. The Rays will likely try to monitor their workloads to keep them fresh for the long haul, and the club will no doubt call upon its depth to help at some point. That means Tampa Bay will probably ask quite a lot of its young pitchers, like Shane McClanahan and Luis Patiño, top 100 overall prospects with little experience in the Majors. And the Rays will rely on versatile, multi-inning arms like Collin McHugh, Trevor Richards and Josh Fleming to bridge the gap to their back-end relievers in the meantime. -- Adam Berry

RED SOX: When and how much will Chris Sale contribute?
Sale is just about to hit the one-year anniversary on his Tommy John surgery, but the Red Sox still haven’t laid out a timetable for his return to action. In fact, Sale has yet to throw off the mound, though the club said that could happen reasonably soon. If the club's ace can be back by close to midseason, it could have a big impact on whether the Red Sox can make a legitimate run at a Wild Card berth. Of course, every pitcher rebounds differently from Tommy John surgery. If Sale can be as effective as John Lackey was for Boston when he came back in 2013, the Red Sox will be thrilled. With three full seasons left on his contract after this one, it stands to reason the Sox will stay on the conservative side with their power lefty. -- Ian Browne

YANKEES: Who is Gary Sánchez?
Sánchez is a two-time All-Star who was the fastest player in AL history to reach 100 home runs. He’s also coming off a season in which he slashed .147/.253/.365 and watched backup catcher Kyle Higashioka start behind the plate for five of New York's seven postseason games. The Yanks wager that Sánchez will return to his early career offensive form, but there’s no guarantee. Sánchez showed glimpses to support both arguments during the spring, mashing tape-measure homers while also chasing sliders in the dirt. His defense has been a constant conversation topic, but what he does over the next 400 or 500 at-bats could determine his future in New York. -- Bryan Hoch

AL CENTRAL

INDIANS: Can the outfield be better than it was in 2020?
The Indians have struggled to receive offensive production from their outfielders over the last few years, but 2020 was the most challenging season for the outfield crew. They had the second-worst wRC+ (54), batting average (.194), on-base percentage (.238) and fWAR (-0.9), while recording the fewest RBIs (62) and homers (11) and lowest slugging percentage (.300) in the Majors. While Eddie Rosario will be the everyday guy in left field, it’s nearly impossible to project what will happen in center. With Oscar Mercado and Bradley Zimmer starting the year in the Minors, Ben Gamel and Jordan Luplow will probably get the majority of the playing time in center. Will they -- and a full season of Josh Naylor in right field -- be able to help bring a boost to the outfield production? The Indians certainly hope so. -- Mandy Bell

ROYALS: The pitching
Who will be the fifth starter? How will the Royals handle the workload question facing every team? Will the bullpen see its success in a 60-game season translate to a 162-game season this year? These are the questions greeting Kansas City's pitching staff come Opening Day. The Royals don't need a fifth starter until April 16, so they can hold off on the first question until then, allowing left-hander Kris Bubic to work through his adjustments until then or turning to long relievers like Jakob Junis or Ervin Santana. And after April 16, the Royals won’t be ignoring the industry-wide uncertainty of how pitchers handle the transition from a shortened season to a full season. Junis and Santana could be used to bridge the gap in innings, too, as the club protects its young arms. The Royals could also call on their depth, like pitching prospects Daniel Lynch and Jackson Kowar. -- Anne Rogers

TIGERS: Can Casey Mize make the jump?
Mize has been ticketed for stardom ever since the Tigers made him the first pick in the 2018 MLB Draft, but the talented right-hander had a rough introduction to Major League hitting last year with a 6.99 ERA in seven starts. More disappointing were his 13 walks over 28 1/3 innings, way out of character for a noted strike-thrower. He appeared on his way to Triple-A Toledo this spring before a strong finish clinched his rotation spot. When he’s on, his five-pitch mix is imposing, but he has to be both aggressive and precise in the strike zone to put his stuff to work. That arsenal includes a splitter that was a wipeout pitch for him when he was pitching ahead in counts in college, though it was inconsistent against big league hitters last year. The more efficient he is, the more innings he can fill, and the longer he can last this season as he ramps up from last year’s 60-game schedule. -- Jason Beck

TWINS: Can Josh Donaldson and Byron Buxton stay healthy?
The health of all others on the roster is obviously important as well, but Donaldson and Buxton take up roles on the Twins’ roster that are particularly hard to fill -- and their injury histories seem to make them the most significant risks. Donaldson was held to 28 games in 2020, the first season of his four-year, $92 million contract, due to recurring calf issues that have plagued him throughout his career. Buxton just couldn’t catch a break again, missing time following a left shoulder injury and a hit-by-pitch to the helmet. Both players can provide MVP-level production when healthy, and both are particularly important to how the roster fits together and performs on defense. The Twins need that kind of upside in their lineup and in the field to not only secure another playoff berth, but finally end their 18-game postseason skid. -- Do-Hyoung Park

WHITE SOX: Can Andrew Vaughn play left field?
When 2021 Spring Training began for the White Sox, the question was whether Vaughn could handle the designated hitter role with just 245 Minor League plate appearances on his resume to go with his work at the team’s alternate training site in Schaumburg, Ill., last season. But Eloy Jiménez rupturing his left pectoral tendon will sideline the slugger for five to six months, and the unfortunate injury opened up the outfield possibility for Vaughn, the club's 22-year-old No. 1 prospect. Vaughn made his left field debut against the Brewers in Cactus League action and has the makeup and seemingly undervalued athleticism to handle the defensive spot at least on a semi-regular basis. -- Scott Merkin

AL WEST

ANGELS: Shohei Ohtani’s health
Despite a blister on his right middle finger that cropped up on Monday, Ohtani is healthy and he proved it with an incredible showing in Spring Training that saw him leading the club in homers at the plate while throwing as hard as 102 mph on the mound. But now he has to prove that he can do it over the course of a full season. Ohtani has thrown just 1 2/3 innings over the last two seasons due to various injuries, so it’ll be a big jump. But the Angels believe he’s ready for it, as he’ll be a normal member of their six-man rotation while also serving as the designated hitter three to five times a week, possibly even in games that he’s pitching. If he can return to form and stay healthy the whole year, it would be a major boost to the club’s postseason chances. -- Rhett Bollinger

ASTROS: How will Myles Straw replace George Springer?
Straw is taking over in center field for Springer, and no one knows what to expect. Straw had a nice spring at the plate and seemed comfortable, leading the club in hits. He’ll be given every opportunity to be the starter in center throughout the season, but the jury is still out. Straw is one of the fastest players in the game and can wreak havoc if he can draw some walks and keep hitting. No one can replace Springer’s production, but Straw could help the Astros in many ways if he’s able to get on base consistently. -- Brian McTaggart

ATHLETICS: A.J. Puk
The 2020 season was expected to see Puk, Oakland’s No. 2 prospect, evolve into a co-anchor atop the A’s rotation alongside Jesús Luzardo. But while Luzardo established himself as a big league starter, Puk’s arm issues popped up again, ultimately leading to surgery in September to clean out bursitis in his left shoulder. Easing his way back this spring, Puk was viewed as a strong candidate for the rotation at the start of camp, but the left-hander has seen his fastball velocity decrease from the 97.1 mph average he showed with Oakland as a reliever in '19 to around 92-93 mph in his Cactus League outings. He’s also struggling to command his pitches, which A’s manager Bob Melvin indicated needs to be improved in order for him to pitch effectively in the big leagues. Having thrown just 36 2/3 innings since '19, Puk might still need to shake off some rust before he can stick in Oakland for the long term. -- Martín Gallegos

MARINERS: Can Seattle take another big step forward?
The Mariners impressed even themselves after finishing in third place in the AL West last season, just two games behind the second-place Astros. That’s not suggesting that Seattle’s roster was as talented as Houston’s, but the Mariners' 27-33 record was a positive sign for a club currently in a multiyear rebuild, which now enters Year 3. Seattle has spent the past two seasons acquiring, gauging and developing young talent. The 2021 season will lean more toward the latter, but many of those blue-chip prospects who fans have been hearing about the past two years are on the brink of the big leagues, which begs the question: Just how close is Seattle to contending? General manager Jerry Dipoto has been cautious with his words when speaking of the club’s realistic goals for 2021, saying that “competing for a playoff spot” is attainable. Translation: Somewhere approaching .500 and playing in meaningful games in the final two months would be a success. With Kyle Lewis up and already doing big things, and with Jarred Kelenic and Logan Gilbert coming soon, can the future faces of the franchise help the Mariners make another big push? -- Daniel Kramer

RANGERS: Almost everything
But the biggest question mark may be how the Rangers’ bullpen will play out following the injuries to José Leclerc and Jonathan Hernandez. The closer role is up in the air, but manager Chris Woodward said the club is still working through how to utilize pitchers in that particular spot. The rest of the bullpen will be a work in progress, likely to include John King, Brett de Geus and Josh Sborz early in the season. The rotation, while not perfect, has more structure at this point in the spring and has potential to exceed expectations in the regular season. -- Kennedi Landry

NATIONAL LEAGUE EAST

BRAVES: Austin Riley
Given Drew Smyly totaled just 26 1/3 innings (21 1/3 as a starter) last year, there is plenty of uncertainty surrounding him as he enters a one-year, $11 million contract. But the club’s starting pitching depth can overcome any struggles he might have. So the more influential unknown might be Riley, who needs to more consistently create value with his tremendous power. Riley reduced his strikeout rate last year and he has become far less susceptible to sliders. If he lives up to his potential, this lineup will have the depth necessary to once again be one of the game’s best. -- Mark Bowman

MARLINS: The bullpen
It would be too easy to go with the young starting pitching, so how about the relief corps? Miami made it an offseason priority to revamp its beleaguered bullpen (5.50 ERA in 2020). The club added strike throwers with postseason experience in Anthony Bass, Dylan Floro, John Curtiss, Ross Detwiler and Adam Cimber. Floro and Curtiss even competed against each other in last year's World Series. This group won't accumulate a ton of strikeouts, so the hope is that the defense will play well in support. With more depth than in years past to prevent overtaxing pitchers, will it be enough to win more close games? -- Christina De Nicola

METS: Noah Syndergaard
Although the Mets remain confident that Syndergaard will return from Tommy John surgery in June, it’s difficult to project how he’ll fare in his first half-season back. Syndergaard’s velocity should be fine; he was already throwing in the mid- to upper-90s in Spring Training. But what about his command? What about his durability? The Mets will have to wait and see, even while counting on Syndergaard to be a key member of their rotation in the second half (and if all goes well, the playoffs). If he’s anything close to the Syndergaard of old, he’ll team with Jacob deGrom, Marcus Stroman and Carlos Carrasco to form a potent mix of frontline starters. -- Anthony DiComo

NATIONALS: Starting third baseman
For the second spring in a row, the Nationals gave Carter Kieboom the opportunity to earn the starting third base job, but the club optioned the 23-year-old to Triple-A Rochester on Saturday. He started 30 games at the hot corner last season and hit .202. Manager Dave Martinez had decided to take a look at shifting Starlin Castro from second to third, but the experiment has been limited to one game after Castro sustained a mild left hamstring strain. It remains to be determined when Castro will be cleared to play (the goal is Opening Day), but in the meantime, the Nationals selected veterans Jordy Mercer and Hernán Pérez to the Major League roster on Saturday, and both -- along with utility man Josh Harrison -- could play second or third. -- Jessica Camerato

PHILLIES: The bullpen
The Phillies had the worst bullpen in baseball in 90 years in 2020. How much better will it be in 2021? It should be better, based on the simple fact it can't possibly be worse. But the Phillies found some talent in the offseason. Left-hander José Alvarado and right-handers Archie Bradley, Brandon Kintzler and Sam Coonrod are newcomers to the eight-man bullpen. Even if the Phillies are only marginally better than last season, it could be a major boost for a team that finished tied for fifth in baseball in scoring. -- Todd Zolecki

NL CENTRAL

BREWERS: Lorenzo Cain
In 2018, Cain was an All-Star and finished seventh in NL Most Valuable Player Award balloting. In '19, he won his first Gold Glove Award. But in '20, Cain elected to step away one week into the season over concerns about COVID-19 and a desire to rekindle his faith. That means he’s something of an unknown heading into '21, especially since he missed the bulk of Cactus League play due to a strained right quadriceps. Cain returned with approximately a dozen games left on Milwaukee's spring schedule and began a quick ramp-up toward the regular season. If he can get his legs back under him, can reacclimate to Major League pitching and can fend off the presence of another Gold Glove center fielder in Jackie Bradley Jr., then Cain could prove to be one of the players most critical to the Brewers’ success this season. That’s a lot of ifs for a player who turns 35 on April 13. -- Adam McCalvy

CARDINALS: Matt Carpenter
The Cardinals entered camp with the hope Carpenter could potentially play his way into a starting role, which would be at second base. That has not happened. Carpenter is just 1-for-33 with 13 strikeouts against seven walks this spring. He’ll start the year on the bench, making spot starts at second -- primarily against righties -- with Tommy Edman sliding to the outfield. But it’s a conundrum: How do the Cards put out their best nightly lineup, not wanting to suffer from a lack of production from Carpenter, but still get him at-bats to hopefully light a spark? -- Zachary Silver

CUBS: Is this the core’s last hurrah?
As Javier Báez, Kris Bryant and Anthony Rizzo have continued to march toward free agency -- all three are eligible to hit the open market next offseason -- there have been constant rumors, reports and speculation about which direction the Cubs are going. The players have grown used to being asked, "Could this be the last ride together for the 2016 World Series core?" But now, that question is very real. The offseason trade that sent ace Yu Darvish to the Padres for, in part, a package of young prospects made it crystal clear that the Cubs have one eye on the long-term plan. That makes this season a potentially critical transitional year in the franchise’s timeline. The team's collective success (or struggle) in the first three-plus months of this season will undoubtedly impact how Chicago approaches the Trade Deadline, or any still-unsettled extension talks. -- Jordan Bastian

PIRATES: Can Mitch Keller become the go-to guy?
Keller has long been the Pirates’ pitcher of the future, stemming from his time as the No. 1 prospect in the organization, per MLB Pipeline. But he’s largely been inconsistent in his first two years in the Majors. In 2019, his ERA was very bad (7.13) when his expected ERA was phenomenal (2.76). In '20, his ERA was stellar (2.91) despite his xERA rising sharply (6.17). Can these trends even out to produce a reliable front-of-the-rotation arm for the Pirates to build around? Keller will need to clean up his walk rate, which jumped to 20.7% last season, to help move the needle toward that future. He’s been successful and struck out batters at a high clip when he stays around the zone, even if he’s given up a few homers. -- Jake Crouse

REDS: What will Jonathan India do as a debuting rookie?
India, ranked by MLB Pipeline as Cincinnati’s No. 5 prospect, opened this spring in the organization’s early Minor League camp, but he impressed so much -- offensively and defensively -- that he not only got promoted to big league camp, but put himself in position to earn a spot on the Opening Day roster. India’s success at the plate and at second base, along with Eugenio Suárez’s improved fitness, enabled the Reds to rework their infield plans. Now, Suárez will be the shortstop while Mike Moustakas takes third base and India mans second base. The move will give the Reds a chance at having more offense. For India, he would be skipping Triple-A after there was no 2020 Minor League season and he will be tasked with learning the league and making adjustments like any rookie. -- Mark Sheldon

NL WEST

D-BACKS: How good is this pitching staff?
One of the things that general manager Mike Hazen has said repeatedly is that for the D-backs to be good, their pitching staff needs to lead the way -- but there are plenty of questions about that staff going into the season. With the rotation, Madison Bumgarner seems to have regained some velocity this spring, which would be a good thing for the D-backs. Meanwhile, Arizona will have to replace the injured Zac Gallen for at least the first two to three times through the rotation, and Luke Weaver will look to put a disastrous 2020 campaign behind him. The bullpen also has its share of question marks. Veteran Joakim Soria figures to be the closer, but the team will rely on several relievers, like Stefan Crichton and Kevin Ginkel, who do not have long big league track records. -- Steve Gilbert

DODGERS: Kenley Jansen
If you ask the Dodgers, they still believe Jansen has what it takes to be an elite closer. That’s why they wasted no time in naming him the closer this season. If you ask Jansen, he believes the same. But if the way last year ended is any indication of what’s to come, there are some question marks surrounding Jansen heading into the 2021 season. After battling COVID-19, Jansen came back and was dominant for the first month of the season, posting a 1.23 ERA with nine saves in 16 appearances. Things started to change in September. Jansen battled command issues (he finished with a career-high 1.15 WHIP) and his velocity kept declining. Because of that, the Dodgers mostly leaned on Julio Urías when it mattered most in the postseason. Manager Dave Roberts has continuously said Los Angeles' bullpen is better when Jansen is pitching well in the ninth. That’s why it’ll be Jansen’s job again in ‘21. But with a plethora of quality options in the bullpen, the Dodgers will continue to monitor Jansen, who looked sharp this spring. -- Juan Toribio

GIANTS: How will the starting rotation hold up?
The success of the 2021 Giants will largely hinge on their starting rotation, which was a weak spot for the club last year. Kevin Gausman and Johnny Cueto will return to anchor the top of the rotation, and San Francisco brought in some much-needed depth by adding Anthony DeSclafani, Alex Wood and Aaron Sanchez on one-year deals this offseason. It’s a talented group, but it also carries some risk, as the Giants will be counting on bounce-back seasons from Cueto, DeSclafani, Wood and Sanchez, who missed the '20 campaign while rehabbing from right shoulder surgery. There is reason for optimism, though, as the Giants have established a reputation for rehabilitating pitchers and helping them unlock their full potential in San Francisco. The emergence of Logan Webb has been one of the best developments this spring, so he could also be ready to take a big forward and establish himself as a quality Major League starter in '21. -- Maria Guardado

PADRES: Dinelson Lamet, Chris Paddack and MacKenzie Gore
The Padres' offseason acquisitions of Yu Darvish, Blake Snell and Joe Musgrove solidified their rotation as one of the best in the sport. Know what might make it truly elite? The last two or three spots. Consider the other high-ceiling arms in the mix: Lamet is a certifiable ace and he is building his way back from a right elbow injury. He could return by late April. Paddack believes he's made a few adjustments that might help him rediscover his dominant 2019 form. Gore is the top-ranked pitching prospect in baseball, and appears to be approaching a breakthrough. If a few things break their way, the Padres might have one of the most dominant rotations in recent memory. -- AJ Cassavell

ROCKIES: When Brendan Rodgers is ready to play, will he be ready to produce?
Rookie second baseman Rodgers will not begin providing answers until he returns from his right hamstring injury. But when he does, he’ll have a chance to reward Colorado for selecting him third overall in the 2015 MLB Draft. Rodgers’ stints with the club in '19 and '20 were curtailed because of right shoulder injuries, and there was a hamstring injury late last season. This spring, however, Rodgers finally seemed comfortable and confident. The tight, tentative swing the Rockies have seen during his brief big league appearances was replaced with the quick, confident swing the Minor League staff has been watching for years. There was also a looseness and willingness to take chances defensively and on the bases. -- Thomas Harding