Ruben Tejada or Luis Castillo? Pick Your Poison.

Two weeks ago, mostly everyone was singing the praises of Ruben Tejada. He appeared to be holding his own at the plate, while providing the best defense seen at the position in a decade.

Since than, Tejada’s come crashing back down to earth. Overall, in 101 plate appearances, he is hitting .221/.299/.267 (.566 OPS. .255 wOBA.) If Tejada qualified, he would be tied for the worst hitting regular in all of baseball with Cesar Izturis (.569 OPS. .255 wOBA).

This is hardly surprising. Here are some of Tejada’s projections coming into this year, including his MLE from AAA this year:

MLE: 173 PA .254/.292/.312 .604 OPS.

Chone: 450 PA  .237/.291/.316 .607 OPS. .273 wOBA -20.7 wRAA

ZIPS: 568 PA .247/.299/.324 .623 OPS. .283 wOBA -21.5 wRAA

At the pace he is is currently at, Tejada would be worth about -40 runs below average over a full season (600 plate appearances). A reasonable rebound resembling his Chone or ZIPS projections, however, puts him at about -28 runs below average over 600 plate appearances.

Meanwhile, in 580 plate appearances last season, Luis Castillo posted a .302/.387/.346 line, with a .337 wOBA. ZIPS projects him hitting a similar .283/.364/.348 with a .330 wOBA the rest of the way.

Castillo was worth 1.5 wins last year (15 runs above average). To match that value, Tejada would probably have to save about 20 runs (or somewhere around 10, with half the season left to play) defensively to compensate for Castillo’s advantage at the plate.

Given Tejada’s defensive prowess, that might be possible, but he has his work cut out for him. According to Fangraphs, only four second baseman have saved 15 runs or more since the stat debuted in 2002:

Chase Utley: 18.4 (2008)

Brandon Phillips: 16.5 (2007)

Chase Utley: 15.7 (2005)

Orlando Hudson: 15.9 (2004)

Further, even if Tejada is capable of such a feat, he better have luck on his side as well. UZR is notoriously inconsistent on a year-to-year basis, and small sample sizes are dangerously misleading. For instance, Dan Uggla, who most people agree is abysmal at second, cost the Marlins 11 runs in 2007, saved a run in 2008, cost them 10 in 2009, yet is on pace to save them about 2 this year. In fact, based on 19 games at second, Tejada is actually on track to cost the Mets 14 runs over a full season.

Yet, there are other factors that could play in Tejada’s favor. Before going on the disabled list for good, Castillo was hitting just .241/.347/.277 with a .302 wOBA. Perhaps that can partly be attributed to his .256 BABIP, but his low BABIP may also indicate an increased inability to leg out infield hits, which is a key component of Castillo’s game.

Not to mention, Tejada could improve his production this season. Elvis Andrus put up very similar numbers in the minors at the exact same age, and in his first full season in 2009 he hit .267/.329/.373 with a .322 wOBA. Tejada really has nowhere to go but up, while the slap hitting, aging Castillo will be lucky if he can repeat his 2009 campaign.

Plus, a solid infield defense helps the pitching staff. Having the confidence to pitch to contact aids everyone, but Mike Pelfrey and even R.A. Dickey (52% ground ball rate), would particularly benefit. Last year, Pelfrey posted a 5.03 era. but had an FIP of 4.39. Having Alex Cora and Luis Castillo as his double play combination most of the year, compounded by David Wright costing them ten runs on defense, certainly did not help matters. It is difficult to quantify this effect; maybe saving only 15 runs (7.5 the rest of the way), would be enough when you account for this.

Tejada could definantly use some refining in AAA, where he can work on his pitch recognition, learn to walk more, and fine tune his defensive games. But can he not equally develop at the big league level, where we would at least have a better idea of what to do next year? I do not know.

If Tejada can raise his wOBA to the .300-.305 range (around a .670 or .690 OPS.) or if Castillo regresses to a similar rate, than you can justify Tejada starting, but that is a big if.

What is blatantly obvious, though, is that the Mets should not resign themselves to simply picking their poison if they are serious about contending. Even in the best case scenario for Tejada or Castillo, Kelly Johnson is worth another win. If Ty Wiggington can get his bat going again, even he is an attractive alternative (he could be worth a compensation pick as well).