The New York Mets will try to ease worries about the middle of their defense before the end of spring training.

The reigning National League champions boast a prolific lineup that was eighth in the league in home runs last season. They also have one of the best starting rotations in baseball.

The defense behind that excellent starting pitching, particularly up the middle, is the Mets’ area of greatest concern before the beginning of the season. They were minus-5 as a team in defensive runs saved (DRS) last season, No. 18 in the majors, according to FanGraphs.

Many of the issues last year could be traced back to the defense at shortstop, second base and in center field. They have two new players at those positions this year, but the outlook doesn’t look much better.

Yoenis Cespedes, playing center, is the returning starter from the middle of the Mets defense last season.

He’s a solid defender but does not have great range, and the Mets aren’t good on defense with him in center field. He was minus-4 last year in defensive runs saved above average (DRS) in center field for the Mets, according to Baseball-Reference.com. His DRS in left was just 4.

That showed in the Mets’ World Series loss to the Kansas City Royals. He misplayed a fly ball in the fifth inning of Game 4 to put the Royals’ first run of the game on base.

Mets manager Terry Collins toyed with the idea of playing Cespedes in center field with Juan Lagares in left when the team plays lefty pitchers. Last season the Mets would move him to left field and allow Lagares to play center against left-handers.

The rationale was that letting Cespedes stay at one position would help him be a more consistent defender. Collins said Tuesday, however, that he will “probably” stick with the conventional alignment he used in 2015, according to ESPN.com’s Adam Rubin.

Having to split time between both left and center instead of focusing on one position probably won’t help him. For the Mets to get back to the World Series, Cespedes needs to show he can get closer to the Gold Glove defense he once played.

Cespedes is not the main issue in the middle of the Mets defense, though. Their middle infield could be problematic too.

They signed shortstop Asdrubal Cabrera, another inconsistent defender, to a two-year deal. Cespedes at least had a DRS of 11 between his time with the Detroit Tigers and Mets last year, per FanGraphs. Cabrera was minus-8 in DRS in 2015, according to FanGraphs. That mark was second-worst in the league among shortstops.

The situation at second base is not much better. The Mets traded for Neil Walker in the offseason, whose DRS was also in the negative last season.

When looking at Ultimate Zone Rating (UZR), Cespedes actually looks really good compared to the other two. His UZR of 15.6 was third in the league among outfielders. Meanwhile, Walker and Cabrera were both well below average.

Any one of those players’ deficiencies could be hidden if he was surrounded by plus defenders. Instead, the Mets are taking a chance by playing them all on defense at once. Their hope is that their offensive production and great starting pitching will mask those issues.

They’re trying to address those concerns now, and they will have to answer those questions all season.

They have three games remaining this spring, starting with Wednesday’s matchup with the Washington Nationals. Over those remaining games, they need to continue to show improvement in the middle of their defense and prove it won’t be as much of a liability as people expect.

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