The Post can’t confirm this, but Yoenis Cespedes might have established a new baseball record Friday night, when he agreed to return to the Mets:

Most times changing the identity of the same franchise in a one-year stretch (2).

His acquisition from the Tigers last July 31 elevated the Mets from mediocrity to a serious contender. His return to Flushing nearly six months later, thanks to a three-year, $75-million contract with an opt-out after the first year, lifts them from a hedge to a serious bet.

Favorites to win the National League East? Absolutely. Favorites to win the NL pennant?

You wouldn’t bet even lightly against them.

Look, it will be nearly impossible for Cespedes to duplicate the magic he produced in his three-month fling with the Mets last year. Based on what we know of his streaky nature, there very likely will be times when the currently elated fan base will rue the day it ever met him.

Over the course of 162 games, though — and possibly beyond — Cespedes should prove his worth not only with his offensive production, but also with the trickle-down effect of his presence.

You now can envision a typical Mets lineup that looks something like this: Curtis Granderson RF, David Wright 3B, Lucas Duda 1B, Cespedes CF, Michael Conforto LF, Travis d’Arnaud C, Neil Walker 2B, Asdrubal Cabrera SS and the pitcher. With a bench featuring Alejandro De Aza, Wilmer Flores, Juan Lagares and Kevin Plawecki.

That offense should provide sufficient support to the Mets’ vaunted starting rotation (and their capable enough bullpen). Cespedes’ presence in the middle of the lineup, his willing embrace of being The Guy You Don’t Want To Beat You, gives more room for error to everyone else. For this group, from the injury-plagued Wright to the up-and-down Duda to the young Conforto and d’Arnaud, that feels especially meaningful.

Now, Mets general manager Sandy Alderson made clear recently — when it appeared that re-signing Cespedes was a long shot — he didn’t view Cespedes as a great fit in center field. He isn’t. Yet if you watched Cespedes patrol center field during his time with the Mets, you know that, with the exception of two profoundly bizarre misplays in the World Series, he didn’t embarrass himself out there (and he should play left field against lefties, with the superior Juan Lagares patrolling center field). The same can be said for the Mets’ new middle infielders Walker and Cabrera, neither of whom will wow you with their range but — unlike their immediate predecessors Daniel Murphy and Flores— will make the plays they should make. They’re sure-handed.

Before the Mets acquired Cespedes, the website FanGraphs projected the 2016 Mets to finish 83-79. Now? 86-76. The primary impetus for that, FanGraphs managing editor Dave Cameron confirmed in an email, is Cespedes. The Nationals, at 88-74, still stand above the Mets. For the moment, though, I’ll put the Mets above Washington, which has whiffed this winter in efforts to add Cespedes, Jason Heyward and Ben Zobrist.

Heyward and Zobrist both joined the Cubs, who rank as the consensus favorites to capture the NL. Makes sense; the Cubs won 97 games last year and also have brought aboard veteran starting pitcher John Lackey. But the Mets don’t have to win more games than the Cubs from April through September.

They just have to outlast the Cubs (or the Cardinals, Pirates, Dodgers, Giants or Diamondbacks) in October, and they did that last year by virtue of their dominant starting rotation.

That rotation, with the obvious provision of good health, could perform even better in 2016 with Noah Syndergaard around from the outset, with Zack Wheeler hopeful of returning in the summertime and with Matt Harvey no longer needing to worry about innings limits.

Just call Cespedes “The Transformer.” He transformed the Mets last midseason and now in the offseason. Can he transform them all the way to a parade up the Canyon of Heroes? Far stranger things have occurred in the sports world.