When the Mets re-signed left fielder Yoenis Céspedes to a four-year deal in late November, it counted as a big win for their lineup, but it did little to answer questions about a collection of talented outfielders that don't really fit well together. Curtis Granderson, Jay Bruce and Michael Conforto are all left-handed hitters who profile best in a corner, and Juan Lagares is an excellent defensive center fielder who struggles to hit or stay healthy.
The Mets are trying to alleviate the outfield glut by trading one, likely Bruce, even though teams reportedly prefer Granderson. Assuming they successfully do move one, they've said they'd be willing to get by with some combination of Granderson, Conforto and Lagares in center. Bruce isn't an option there, which is why they'd much rather move him than Granderson.
Maybe that'll be fine. But is "fine" good enough for a team that's clearly positioned to battle Washington for the National League East title? Let's propose a radical idea to help the Mets improve this winter, one that's unlikely, but not unrealistic: Instead of trading one of their three lefty corner outfielders and shoehorning the others into center, why not trade two, and then go get a true center fielder? Not only that, we'll make it payroll-neutral, because they've said that Cespedes was their big splash and they aren't likely to spend more.
It's not as wild as it sounds, because there's a robust trade market for center fielders right now, one of the few positions where that's the case. We'll get to who in a second; first, let's explain why this is the route the Mets should take.

To start with, the Mets were not a strong defensive team last year. With minus-21 Defensive Runs Saved, they were tied for 21st in the Majors. With Cespedes back in the fold, they're bringing back basically the exact same roster, except a year older -- only Conforto and Travis d'Arnaud, among semi-regulars, will be younger than 31.
Though Granderson has said he's willing to play center field, as he did late last season, he'll also be 36 years old in March, and teams simply don't let players of that age play center regularly. To wit: In the six seasons since 2009, when Mike Cameron did it for Milwaukee, no one age 36 or older has played more than 81 games in center. That's not a coincidence, as teams get smarter about aging curves and defense. Forget 36, actually; since 2010, only two players older than 33 have played 81 games in center -- Andre Torres in 2012 and Coco Crisp in 2014 -- each 34 years old.
While it's true that Granderson looked surprisingly decent in center in 2016 (+1 in DRS, +2 in UZR), it was in such a small sample size that it's not that indicative of future performance. Besides, it's now been nearly five years since Granderson last played center regularly, when the Yankees decided to shift him to a corner in favor of Brett Gardner. It's difficult to see him being the one to capably play the position at an older age when no one else has been able to. (Interestingly, he played extremely shallow in center in 2016, averaging 306 feet from home plate, tied for shallowest with a group of outfielders that included Denard Span, Adam Jones, and Andrew McCutchen. Lagares was at 313 feet in center, while Cespedes averaged 314.)
Between them, Bruce ($13 million) and Granderson ($15 million) will make a combined $28 million in 2017, so moving both would clear salary to add a veteran center fielder in another deal, and still have some remaining for the reliever they need, assuming they don't just get one included in one of these trades. Or, perhaps, you keep Granderson to play right field and make Conforto the focus of the deal. Coming up with trade proposals is rarely satisfying, so we'll leave the specifics to you, and instead focus on five possibilities who would look wonderful roaming center in Queens in 2017.

Lorenzo Cain, Royals
It's difficult to find a better fit here than Cain, a right-handed hitter with a roughly league-average bat, who has long been one of the preeminent center-field defenders. We know the Royals are considering deals for their group of players entering the final years of their deals, which is partially how Wade Davis ended up with the Cubs, and the $11 million still due Cain in 2017 would be fine assuming one, or both, of Bruce and Granderson departed. Imagine an outfield with Cespedes in left, Cain in center, and Conforto or Granderson in right.
Jarrod Dyson, Royals
This would be a slightly different approach, because while Dyson isn't close to the hitter that Cain is, he's a better fielder, and he'd also add an element of speed. He has stolen 26 or more bases in each of the past five seasons, despite never playing more than 120 games in a year. Though a lefty hitter isn't as good a fit as a righty for New York, that's less of an issue if you've just dealt two lefty outfielders, and he's going to make less than $3 million in 2017, so the contract is no problem. The center-field defense you could get by platooning Dyson with Lagares might be the best in baseball.
Billy Hamilton, Reds
Speaking of elite speed and defense in center field, there's no one better than the switch-hitting Hamilton, who has reportedly been the subject of trade inquiries. Like Dyson, he's affordable, though the Reds wouldn't give him away lightly. He might just be baseball's best defensive center fielder -- that's right, Kevin Pillar and Kevin Kiermaier -- and while he'll never be a plus hitter, you can at least dream on the fact that he followed up a poor first half with an adequate .293/.369/.333 in 45 games in the second half. If he can hit like that with his speed and defense over a full season, he's a star.

Charlie Blackmon, Rockies
Blackmon has been the subject of many trade rumors, forcing Rockies general manager Jeff Bridich to address them, saying to take them "with a grain of salt." Despite the public declarations to the contrary, it still seems hard to believe that Ian Desmond will play first base regularly, so Colorado could easily trade an outfielder for badly needed pitching. (They reportedly tried to trade him to Toronto for Marcus Stroman.) Blackmon is projected by MLBTradeRumors.com to make about $9 million in arbitration, and while he's been a slightly below-average defender, getting out of the enormous Coors Field outfield would likely help him. He also slugged for more power away from home (.563) in 2016 than he did in Colorado (.540), so he's not a product of altitude.
McCutchen, Pirates
We include him here for the sake of being complete, because while the contract ($28 million over the next two years) sort of fits, the fact that McCutchen just had a very poor season in center himself makes it hard to justify the obviously sky-high return the Pirates would require. There's evidence that positioning made him look worse than he actually was, and he's still an above-average bat who would improve the Mets' lineup. Still, Pittsburgh would want Amed Rosario, New York's No. 1 prospect per MLBPipeline.com, and the Mets have been clear they have little appetite to move him.
The Mets probably won't end up making any of these moves. That doesn't mean they couldn't, though. There are a lot of ways to assemble an outfield.