Since the start of the 2015 season, there hasn’t been a better hitter on the Mets than Yoenis Cespedes. He’s second among position players in WAR to Curtis Granderson, who has played more than 100 more games with the Mets over that span. As soon as he arrived at the trade deadline in 2015, Cespedes became one of the faces of the franchise, and has become a symbol of the endless possibilities of contention for Mets fans.

He’s likely to command one of the largest contracts of the offseason. Cespedes can hit for average, draws a fair number of walks, and hits for power. He plays standout defense in left field when healthy. That said, he’ll also be playing on the wrong side of 30, and may very well be finishing his expensive contract on the wrong side of 35. Cespedes spent all of the 2016 season with a nagging leg injury originally sustained on a diving effort into the stands for a fly ball. Steamer forecasts just 3.0 WAR for him next year. On a certain level, it seems as if re-signing Cespedes would be a mistake for the Mets.

But it wouldn’t be. In fact, re-signing Cespedes is the best move the Mets could make this winter.

At present, the Mets have a full outfield. They exercised Jay Bruce’s $13 million option for 2017, so he’ll be playing right field. Juan Lagares and Curtis Granderson are expected to share time in center while Michael Conforto resumes his place in left. Something would have to give if Cespedes were to return. Cespedes is a brilliant left fielder when he’s healthy, so it makes sense to give him an opportunity to create value in the field. But there are options for Sandy Alderson: he could demote Conforto, move Conforto to first base and part ways with Lucas Duda, or he could trade Bruce and move Conforto to right.

Duda is coming off a season in which he played just 47 games due to a fracture in his lower back, and has been an inconsistent yet productive hitter for the last few seasons. When he’s right, like he was in 2014 and 2015, he can hit somewhere in the neighborhood of 30 home runs and post a wRC+ in the 130s. The sort of back injury from which he’s suffered can create lasting complications. If he’s healthy, though, Duda could be a key offensive player, and one with whom the Mets would be loath to part. It may be prudent to stick with him. Conforto, the team’s first-round pick in 2014, is pegged for a 2017 wRC+ of 113 by the Steamer projections. Meanwhile, Bruce is projected for a below-average 97.

Therefore, it makes the most sense to trade Bruce to clear the way for Cespedes. Bruce has been productive in the past, and may still fare decently as a DH or as an outfielder for a team that plays in a small park. Not only does Conforto project as a better hitter, but he will need regular at-bats, given his strange demotion earlier in the year and his position as an important part of the franchise’s future.

Is moving Bruce worth it, though? Should the Mets instead seek to re-sign Neil Walker and pursue small upgrades at other positions? Alderson has already said that they would be okay with the second baseman accepting his qualifying offer. Walker is currently recovering from a back operation he underwent in September, and if his rehab isn’t progressing well, he may be inclined to take his $17 million and seek a multi-year deal next year after rebuilding his value. That $17 million wouldn’t be an inconsequential amount to the Mets.

Under other circumstances, those considerations might be valid. The Mets are a franchise in win-now mode, however — one that’s depending on an array of talented but surgically repaired starting pitchers. That creates even greater urgency. Plus, three of the other four teams in the division are either rebuilding or stuck in the mud. Only the Nationals represent a real challenge, and may in fact be one of the teams looking to sign Cespedes. What better time is there to double down and pay out for quality players to fill the team’s needs?

As for Cespedes’ projection, there’s even reason for optimism there. His subpar defensive value in 2016 is very likely the product of the aforementioned leg injury and not age-related wear and tear. A healthy Cespedes, strictly limited to left field, should regain some defensive value. (He posted negative marks in both DRS and UZR in his Terry Collins-induced time in center field.)

Will Cespedes almost certainly be a worse player by the end of his deal? Yes, but that’s the case with virtually every free-agent contract. The question of context matters. And the context for the Mets necessitates success in the present. Cespedes is an upgrade over Bruce, and a good candidate to outpace his projections. Retaining Neil Walker, and even possibly pursuing an upgrade at catcher, can’t stand in the way of the Mets’ pursuit of their best position player.

Given the weak free-agent class, there are few options with which to add real talent this offseason. Cespedes is one of them. Without him, the highest projected wRC+ on the team belongs to Duda at 115. But if we assume that Cespedes is able to complement his typically strong offense with the sort of defensive value of which he’s capable, then this should be a no-brainer for Alderson.