The Mets’ early January trade for Francisco Lindor reshaped the middle-infield dynamics of the National League East. In Lindor, the Mets now feature one of the best shortstops in baseball, capable of boosting his new team to its first playoff berth in half a decade.

But Lindor is far from the only middle-infield star in a stacked division. In Washington, Trea Turner has developed into an elite player in his own right, capable of challenging for an MVP Award at some point in his career. In Philadelphia, Didi Gregorius is back for another season of quiet professionalism and production. In Atlanta, Ozzie Albies and Dansby Swanson form one of the most potent duos in baseball. And in Miami, the Marlins feature an intriguing mix of rookie potential and veteran leadership.

Here’s how the middle-infield situations look across the NL East:

Braves
The known: After struggling during the second half of his All-Star season in 2018, Albies tallied a second straight 20-homer season in ’19, while producing a .852 OPS. The 24-year-old second baseman missed half of last year’s regular season with a right wrist injury. But he still showed some pop as he hit eight home runs and produced a .461 OPS over 41 games (postseason included). More importantly, the talented switch-hitter continued to show the strides he’s made from the left side of the plate. The .768 OPS he’s produced against right-handers since the start of '19 is significantly better than the .467 OPS he constructed against them over the last 59 regular-season games of '18.

The unknown: While Albies has at least provided power over multiple seasons, the Braves still don’t know exactly what they have in Swanson as he prepares for his fifth full season as their shortstop. A strong start to the 2019 season was followed by an injury-plagued, disappointing second half. Swanson constructed a career-best .809 OPS, while tallying 10 homers (one every 23.7 at-bats) over 60 games last year. But while the opposite-field power he has shown over the past couple seasons creates encouragement, the fact is this former top overall pick has yet to live up to his potential over a full 162-game season. -- Mark Bowman

Marlins
The known: Miguel Rojas, the club’s unofficial captain, will once again be the starting shortstop entering his seventh season with the organization. In 2020, he was named a Gold Glove Award finalist at the position for the first time. Rojas, who turns 32 on Feb. 24, recorded a career-best slash line of .304/.392/.496 and an .888 OPS in 40 games last year. Not only has he been mentoring prospect Victor Mesa Jr. over the offseason, but he has also been receiving extra maintenance on his shoulder and hip to handle the return of a 162-game season.

The unknown: Second base will be a competition between Isan Díaz and No. 4 prospect Jazz Chisholm, with utility player Jon Berti in the mix. Díaz, the former top prospect who was part of the Christian Yelich trade, slashed .173/.259/.307 in 49 games as a rookie in 2019. When Miami experienced a COVID-19 outbreak, he elected not to play before returning in September and sustaining an injury soon after. Chisholm, who is considered the future shortstop, went 9-for-56 and made some highlight-reel defensive plays upon his callup. He started Game 3 of the NL Division Series, recording a double and a walk. -- Christina De Nicola

Mets
The known: The Mets’ splashiest move of the offseason took place early, when they acquired Lindor in a seven-player deal with Cleveland. Shortstop immediately became a significant strength for the Mets, who will rely on Lindor to start nearly every day at the position. At second base, Robinson Canó’s suspension opened the door for Jeff McNeil to move back to his natural position, giving the Mets one of the better middle-infield tandems in the league. McNeil and Lindor will both hit in the top half of New York’s lineup, perhaps as high as 1-2 in the order, giving the Mets plenty of offensive punch.

The unknown: McNeil won’t discard his other gloves just yet, as there’s always a chance an injury could push him back to third base or left field. If that’s the case, the Mets are well-protected at second base, with Luis Guillorme and Jonathan Villar both capable of playing the position. Guillorme is an excellent defender at both second base and shortstop, while the lightning-fast Villar is a source of speed off the bench. Although there’s theoretically room for both on the Opening Day roster, Villar’s presence puts Guillorme’s spot in jeopardy; the Mets guaranteed $3.55 million to Villar, which means he’s going to be on the Opening Day bench barring injury. But Guillorme is coming off a strong 2020 and deserves some run as well. -- Anthony DiComo

Nationals
The known: The Nationals have one of the best middle infielders in the game in Turner. The electric shortstop has fared strongly over multiple 2021 projection systems as he enters his seventh season in the Majors. Turner ranked first among shortstops and fifth among all players last year with a career-high .335 batting average, which included 16-game and 10-game hitting streaks. He also paced all shortstops in slugging percentage (.588), on-base percentage (.394), OPS (.982) and extra-base hits (31). To that point, Turner led baseball in bolts and tied for fourth in sprint speed in ‘20.

The unknown: Veteran second baseman Starlin Castro’s first season with the Nationals was cut short last August by a broken right wrist. Following Castro’s injury, the Nats turned to top prospect Luis García, who made his Major League debut at only 20 years old. García stepped up and hit .276 in 40 games (35 starts at second). Washington has options at this position, but there also are questions: how many games will Castro play? Manager Dave Martinez described him in December as a “full go.” If Castro is completely healthy, what does that mean for García’s role and his opportunity for playing time on the Major League level? -- Jessica Camerato

Phillies
The known: The Phillies filled a major hole last week when they signed Gregorius to a two-year, $28 million contract. Their alternatives at shortstop, if he signed elsewhere, were lacking. But now that Gregorius is back, Phils manager Joe Girardi confirmed what everybody expected: Jean Segura will be the primary second baseman. It gives the Phillies a solid up-the-middle combo with Gregorius posting a 119 league-adjusted OPS+ last season and Segura posting a 106 OPS+. Scott Kingery will play a super-utility role unless he grabs regular playing time in center field. Infielder Brad Miller could be returning, which would give them additional depth.

The unknown: The Phillies need to be better defensively in 2021. Gregorius tied for 23rd out of 39 qualified shortstops with -1 outs above average, according to Statcast. The Phils think he can be better than that. Can they help Gregorius, possibly with different positioning? Perhaps. Meanwhile, Segura tied for 10th out of 47 second basemen with 2 OAA and Kingery ranked last with -4, which was a disappointment. -- Todd Zolecki