The postseason field is set. And as we look forward to an October filled with surprises, we asked the beat reporters covering the 10 playoff teams for MLB.com to predict a breakout star for that team.

Here are their expert opinions, listed alphabetically by league:

AMERICAN LEAGUE

ASTROS: RHP Luis Garcia

Garcia came out of nowhere last year -- he hadn’t even pitched above Class A ball -- and made his Major League debut during the COVID-shortened season. He pitched so well (2.92 ERA in five games) that he wound up starting Game 5 of the AL Championship Series, which set him up to be in the rotation to start this year. He’s already shattered his career-high in innings pitched but hasn’t shown signs of slowing down. Garcia has blossomed into one of the top rookies in the AL this year, going 11-8 with a 3.30 ERA and 1.17 WHIP in 155 1/3 innings. He ranked among AL rookie leaders in wins, innings and strikeouts. -- Brian McTaggart

RAYS: LHP Shane McClanahan

Nobody will match last year’s run by Randy Arozarena, who enjoyed the quintessential October breakout, and nobody will be surprised if rookie phenom Wander Franco goes wild at the plate in his first postseason. Top prospect Shane Baz could turn into this year’s version of 2008 David Price, if not more. A lot of people are going to learn starter Drew Rasmussen’s name, too. But the pick here is McClanahan, who made history last year by becoming the first player to make their MLB debut in the postseason.

The 24-year-old lefty has a four-pitch mix with elite stuff, including a fastball that touches triple digits and two swing-and-miss breaking balls, and he’s shown a commitment to using it in the strike zone. He’s also been impressively consistent, allowing more than three runs only once and working fewer than five innings only once while posting a 3.09 ERA in a 15-stretch start from June 15 through Sept. 19. The Rays won’t ask for too much from their starters, but McClanahan is going to turn some heads with whatever he does in October. -- Adam Berry

RED SOX: OF Alex Verdugo

The fiery Verdugo should thrive in the environment of playoff competition. The more heightened the atmosphere, the better Verdugo seems to play. And, offensively, he is often at his best with the game on the line, and he showed that with a two-run double on Sunday to spark the Red Sox’s comeback against the Nationals to clinch an AL Wild Card spot. This will be Verdugo’s first trip to the postseason, so you know he will be up for it.

Though Verdugo has power, he hasn’t displayed it quite as much as expected this season. That’s fine with the Red Sox, as his line-drive swing has him on the bases frequently, and he topped 30 doubles. Defensively, Verdugo is a weapon in left but not the same player in center. Expect him to get all of his playing time in October in left field. Because he hasn’t been effective against lefties this season, Verdugo will likely start against mainly righties. However, this makes him an intriguing option off the bench for manager Alex Cora in games he doesn’t start. -- Ian Browne

WHITE SOX: OF/DH Gavin Sheets

It’s tough to include someone such as Luis Robert, Eloy Jiménez or Yoán Moncada in this group because they’ve already established themselves as premium frontline Major League talent. So the nod goes to Sheets, who figures to get playing time at the very least against right-handed pitching in the postseason. Sheets worked diligently to take this next step forward during this past offseason after not being invited to the team’s alternate site training facility in ’20, and he posted 11 home runs, eight doubles, 34 RBIs and an .830 OPS in 54 games with the White Sox. He’s a true left-handed power bat, which the White Sox otherwise don’t really have, and he hit .268/.344/.556 against right-handed hurlers with all 11 of his homers in 160 plate appearances. -- Scott Merkin

YANKEES: LHP Nestor Cortes

The mustachioed Cortes has become the folk hero of the Yankees’ push to the postseason, his image even emblazoned on a T-shirt depicting him as Mario from the Nintendo classics. Cast off by the Yankees, Orioles and Mariners over the previous three seasons, Cortes has unlocked his potential this year, keeping opponents off balance with a dizzying array of offspeed pitches and funky deliveries. Cortes projects to be included in the Yankees’ rotation if they advance past the AL Wild Card Game, and it would be no surprise to see him run off a string of effective performances. Cortes also could be utilized out of the bullpen, using his unique skills to limit hard contact and soak up important outs in long relief. -- Bryan Hoch

NATIONAL LEAGUE

BRAVES: LHP Tyler Matzek

The baseball world got a glimpse of Tyler Matzek during last year’s postseason. But Matzek’s great story of perseverance might be even better respected as he enters this year’s playoffs as Atlanta’s top relief option. The lefty hasn’t been elevated to closer status, but when available, he is used to go through the middle of an order or handle other high-leverage threats in the middle innings. Matzek’s dominance since the All-Star break has added to the greatness of his story, which was highlighted when he returned to the Majors last year for the first time since 2015.

The reliever tasted some success as a Rockies starter in 2014, but developed the yips the following year. He spent nearly five seasons overcoming this debilitating issue and the depression it brought. The Braves found him pitching in an independent league in 2019, but until he impressed while being used as an extra in some 2020 Spring Training games, there was never any thought he’d be more than just organizational depth. -- Mark Bowman

BREWERS: LHP Aaron Ashby

The 23-year-old left-hander, No. 8 on MLB Pipeline’s latest list of the Brewers’ top prospects, has a chance to be this year’s version of 2018’s Brandon Woodruff, Corbin Burnes and Freddy Peralta -- all of whom logged important relief innings during the postseason as they were just being introduced to the Major Leagues. All three have since developed into front-line starters for the Brewers, who believe strongly that Ashby is on the same path.

Ashby made his Major League debut in a spot start against the Cubs on June 30, and it was a disaster (2/3 of an inning, four hits, seven runs, four earned, three walks, zero strikeouts) but since then he’s been sensational. Said manager Craig Counsell: “The most impressive thing, frankly, is how he handled life after his first day after he pitched. That's not easy. That was a tough situation. I don't think anyone would have been surprised if it had knocked him down, but it hasn't at all and that was really impressive. He's come back better, really.” -- Adam McCalvy

CARDINALS: OF Tyler O’Neill

Both expectations and questions have been rampant over O’Neill’s career. The Cardinals acquired him from the Mariners at the 2017 Trade Deadline in exchange for Marco Gonzales, believing he had a sky-high ceiling, a unique combination of both speed and strength. Thoughts of a 40/40 potential were not out of the question. But some major strikeout numbers have also followed the Cardinals’ left fielder. That’s until he cleaned those up in 2021 -- and then some. O’Neill hit .286 with an on-base percentage of .352 and an OPS+ of 150 -- consistently impressive and productive numbers. The home runs he hits -- a career-high 34 -- are prodigious. He’s burst onto the scene this season, and there’s no reason to think he won’t continue to do so in October. -- Zachary Silver

Dodgers: LHP Alex Vesia

Vesia, who was acquired from the Marlins in the offseason, struggled to get going at the beginning of the season, but has been one of the best relievers in baseball since returning from Triple-A Oklahoma City. Since July 9, Vesia established himself as the top left-handed option in the L.A. bullpen, posting a 0.92 ERA with 38 strikeouts in 31 appearances (29 1/3 innings). The Dodgers will count on Vesia a lot over the next couple of weeks if they advance past the NL Wild Card Game. -- Juan Toribio

GIANTS: OF LaMonte Wade Jr.

Acquired from the Twins in exchange for Shaun Anderson in February, Wade has been a revelation for the Giants this year. He never hit more than 11 home runs in a single Minor League season prior to this year, but ended up tied for fourth on the team in homers (18) and has earned the nickname “Late Night LaMonte” due to his penchant for coming through with clutch hits in late-inning situations. While he’s primarily an outfielder, Wade is also capable of playing first base -- a position he manned in college -- and could play a critical role in helping the Giants withstand the loss of Brandon Belt, who suffered a fractured left thumb after being hit by a pitch during a game at Coors Field on Sept. 26. -- Maria Guardado