The current conventional wisdom is that the AL is the better of the two major leagues.  The Giants seem to be taking advantage of this fact.

Aubrey Huff, Juan Uribe, Pat Burrell, and Santiago Casilla are all AL cast-offs who seem to have rediscovered their old glory coming (or returning) to the NL.  In the case of Burrell and Casilla, in particular, the sample sizes are too small to draw any firm conclusions.  However, even with them, the changes have been so dramatic that they’re worth commenting on.

Juan Uribe, in his five seasons with the White Sox from age 25 through 29, had the following OPS numbers: .833, .713, .698, .678, and .682.  That looks an awful lot like a one-way ticket to palookaville.

Yet upon arriving in San Francisco, Uribe had .824 OPS last season and an .836 OPS so far in 2010.  At age 31 this season, Uribe isn’t yet past his prime years.  Also, his numbers could drop suddenly going forward this year, just as Aaron Rowand’s have in the last month.  Still, the change is striking.

Aubrey Huff is 33 this year, which is definitely past his prime years, but not so old that he couldn’t be having a last-hurrah season.  In 2008 at age 31, Huff had a .912 OPS, the second highest of his career, for the Orioles.  Last year, his OPS fell to an awful-for-a-first baseman .694.

Yet after tonight’s two-home run performance against the A’s, Huff has a .926 OPS so far in 2010.  Now, I don’t expect Huff to have a .926 OPS come season’s end.  Nonetheless, the change is striking.

In Pat Burrell’s last year with the Phillies, he had an .874 OPS.  With the Rays last year, his OPS plummeted to .682, and this year in limited playing time, his OPS fell again to .625, at which point the Rays released him.  So far as a Giant, Burrell has a 1.054 OPS.  Sure, it’s only 24 at-bats as a Giant, but the change is again striking.

In his three seasons as a regular reliever for the A’s, Santiago Casilla had ERAs of 4.44, 3.93, and 5.96 last season, which caused the A’s to send him packing.  In 12 2010 appearances for the Giants, Casilla has an 0.96 ERA with two saves, four walks, and 15 Ks in 9.1 IP.  It’s an extremely small sample size, and the A’s arguably gave up too soon on Casilla—who throws extremely hard—but the change is striking.

The most reasonable theories I’ve heard for why the AL is the better league, is that the best teams in the AL are the wealthiest in baseball, and the worst teams are not as bad as the worst teams in the NL.  Another theory I’ve heard is that the NL is a fastball league—teams look for fastball pitchers and hitters who can hit the fastball.  In the AL, pitchers are alleged to throw more breaking balls.

I haven’t seen the data (or read any recent articles by those who have) to render an opinion on the last point.  However, I do suspect that certain players play better in one league than in the other. 

For what it’s worth, Casilla throws a mid-90s fastball, which may account for his sudden success in the NL.  Of course, it could just be that he’s finally found the command that bullet-throwers have more time to find before they start to lose their good fastballs.

Interestingly, Barry Zito, whose famed best pitch is his curveball, is a player who has pitched worse since coming over to the Giants from the AL. 

While I think that Zito’s problems the last two years have more to do with the heavy workloads he had as a starter for six seasons in Oakland (his numbers had started to drop before he left), and the fact that pitching in Oakland, which is one of the best pitchers’ parks in MLB, masked his decline in the seasons immediately before he became a free agent, it’s still obvious that his record in the NL (until this season at least), doesn’t compare to his record in the AL.

The question, I guess, is whether the Giants have recently identified something that has enabled them to pick former AL players likely to have better success in the NL or whether they’ve just been lucky.  I suspect more of the latter than the former.

However, the Giants have been extremely successful the last couple of seasons in identifying cast-off relief pitchers who have really been able to help them: Justin Miller and Brandon Medders last year, and Guillermo Mota, Santiago Casilla, and Denny Bautista in 2010. 

It’s helped to balance out somewhat oft-injured veterans like Mark DeRosa, Freddie Sanchez, and Edgar Renteria, who the Giants have committed way too much money to the last two seasons.

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