Now most news sources are reporting that the Mets intend to sign Sosa to a major league contract worth $1.25 million. Even though the Mets are guaranteeing him that money, if he winds up pitching poorly they can always cut or trade him without having to wriggle their way out of an albatross contract.
But is Sosa any good? Historically, he certainly has not been. He owns a career ERA of 4.61 and strikeout-to-walk ratio of 5.81-to-4.23. He has also allowed 1.38 homeruns per game (nine innings) over the course of his career. Twice in five seasons he has posted homerun rates of less than one: in 2003 when it was 0.98 and in 2005, with the Braves, when it was 0.81 and his ERA was just 3.05, the best of his career by more than a run.
That 2005 season looks good on certain types of paper. His 13-3 record and solid ERA certainly *look* nice. Dig a little deeper and we see that his FIP that year was 4.53, almost a third of a run higher than the National League average of 4.22 (note: that average includes relievers, who generally have lower ERAs than starters, so Sosa's ERA relative to the league is a big misleading). He had an abnormally low (for him) homerun-per-flyball rate that season, which can be somewhat attributed to Turner Field. He'll be pitching at Shea this year, which is typically a tough park for right-handed flyball hitters, a good park for left-handed flyball hitters, and a slight pitcher's park overall.
Even though this is giving guaranteed money to a mediocre pitcher, the terms in both length and value of it make it far from prohibitive. I'm not sure where exactly he fits into the pitching staff's plans, though his history of pitching unspectacularly as both a starter and reliever make him more versatile than someone who was just mediocre at one or the other. The best spot for him may be as a long man/spot starter, though I was under the impression that they already had a bunch of those in guys like Dave Williams, etc.
If he can keep the ball in the park either by luck or by skill he can be at least reasonably effective, so long as Willie Randolph gives him the best opportunity to succeed. He has not been particularly effective against lefties the past three seasons, allowing a .282/.368/.519 line in 632 at-bats against southpaw-swingers. Barring injury, the Mets have plenty of one-inning-or-less guys in the bullpen in Billy Wagner, Aaron Heilman, Duaner Sanchez, Pedro Feliciano, et al, so unless the Mets plan on using him as a ROOGY, it's still not clear to me how they will get $1 million worth of baseball out of this guy.