Pete A. has returned from his furlough (and here I thought that only happened to school employees), to post an interesting take on the addition of A-Rod to the Yankee's lineup.
While everything has small sample size stamped all over it, I'm always up for an exercise in inductive reasoning.
Pete notes that in the first 28 games, the Yankees went 13-15 while averaging 5.64 runs per game. In the 17 games since the return of Arod, the Yanks have maintained that identical run production, though they have slugged about 50 points higher and OBP'd 15 points lower.
Pete concludes:
what has changed is that the Yankees are a more confident team offensively. That flurry of walk-off wins is evidence. I realize, of course, that there are dozens of variables including the pitchers they faced, the opponents, the ballparks, injuries, etc. But it surprised me that the offense stats were basically the same.
To his credit, he does acknowledge that "the pitching obviously has improved, that's why they're winning."
But allow me to further disagree with Arod having added any value yet.
In the first 23 games of the season, a fellow named Jorge Posada hit .312/.402/.584.
In his 17 games back, Arod has hit .259/.411/.672.
Obviously, it's unrealistic to expect either player to continue to hit at such a pace, but so far Arod has made up for the absent Jorge. Furthermore, since I expect the cooled off Arod to outhit the cooled Posada, having Arod healthy is worth more than Posada healthy. This is especially true when you consider that Arod's replacements hit .001/.002/.001*, while Jorge's replacements have combined roughly .270/.310/.330*.
*(Numbers not to scale).
It may be that Tex is getting better pitches to hit with Arod behind him rather than some combination of Matsui, Nady, Swisher, Posada. But I'm not willing to concede that it's the reason for Tex's awakening without some empirical evidence.
The really impressive thing is that Arod has had all or nothing results at the plate. A-Rod's 5 for 5 lifted his average 70 points; before Monday he had 10 hits, of which 8 were homers, a single and a double. As his bat finds a more measured approach he will improve the team- while he took 13 walks in 68PA, Arod's strength has been as a slasher, not as an OBP machine.
For the Yankees, the real difference will come in June when Jorge returns to the lineup, even if that puts Matsui on the bench more often.