Mets Add Bay

The inevitable finally happened today, as the New York Mets added LF Jason Bay on a four-year deal with a vesting option for a fifth. Bay will, of course, be the next starting left fielder for the Mets and will likely push Fernando Martinez to either the bench or the minor leagues.

This deal definitely improves the Mets’ offense for 2010. Bay’s roughly +30 run bat replaces Martinez’s, which only projects at -5 to -10 runs against average. Bay’s bat combined with Jose Reyes, Carlos Beltran, and David Wright gives the Mets a scary top of the order for opposing pitchers.

That’s about where Bay’s effectiveness ends. Bay’s defense is questionable at best. Even with the park effects with the Green Monster on Boston LFs, it’s hard to imagine Bay as an above average defensive left fielder. UZR has Bay at -54.7 runs over four years, including 1.5 poor years in Pittsburgh. TotalZone thought Bay was decent last year, at +4, but still rates him at -40 runs overall in the last four years. The Fan’s Scouting Report has Bay as a below average LF.

His non-SB baserunning numbers do look decent, as he is roughly a +1 to +2 runner by Baseball Prospectus’s EQBRR statistic. Still, that’s pretty insignificant, and it’s safe to say that his value comes from his batting.

Of course, the real interesting point of the contract is the dollar value. The Mets will pay Bay 66 million dollars over the four guaranteed years of the contract, and the vesting option reportedly pays an amount similar to that 16.5M AAV. Given the current market, $3.5M per WAR, the Mets are expecting 4.5 wins per season out of Bay. Is Jason Bay the type of tier-2 superstar that deserves this contract?

As a 31-year-old with what we tend to call “old people skills” – high power, poor defensive range and average-at-best speed – Bay can be expected to decline at a faster rate than the average player. He has averaged 2.1 wins per season since 2007, although giving higher weight to his better 2008-2009 seasons vs. his replacement-level 2007 gives a weighted average closer to 2.8-3.0 wins, close to the 3.1 wins that the fans have projected him to at the time of this writing. Yes, it’s possible his defense is better than UZR/TZ/FSR think, but it would take a 15-20 run swing in his defensive value to produce market value with this contract. This is without even considering the effect that playing in Citi Field could have on his offensive value.

The Mets can afford to overpay given their place on both the revenue curve and the win curve. However, this contract could really hamstring their situation in 2012/2013 as Bay declines, and it could also severely hamper the development of Fernando Martinez. This move appears to be one of the more significant overpays of the offseason, and it by no means vaults the Mets into the playoffs. Much needs to go the Mets’ way for this contract to work out as planned, and it appears that this is just yet another example of Omar Minaya overpaying for a veteran presence.