If Santana was to come to the AL East, what could be expected of him? Traditionally, the AL East has been one of the more offensive-packed leagues in baseball. But the level of competition in the AL Central has been on the rise. So first I'll take a look at how the AL Central and AL East compare offensively.
In 2007, the AL East had two of the top five offenses in baseball. It also had the 15th, 16th, and 17th best offenses in baseball respectively. The average AL East team last year scored 825.2 runs.
On the other hand, the AL Central had two of the top ten offenses in baseball. It was also home to baseball's 25th, 27th and 28th best offenses respectively. The average AL Central team last year scored 763 runs. BUT Johan Santana played for the Twins, so he never got the benefit of facing their weak offense. So the average division rival that Santana faced in 2007 scored 774.25 runs.
That total is still significantly lower than the average offensive output of AL East teams. But then you must also consider the team that Santana would be playing for in the AL East. Fortunately for Santana, he would be heading to one of the top five offenses in baseball, and so would never have to face them.
If Santana went to the Red Sox, and had to face division teams including the Yankees, Blue Jays, Orioles and Devil Rays, the average offensive output for those teams last year was 814.75 runs. And if Santana went to the Yankees, only had to face division teams including the Red Sox, Blue Jays, Orioles and Devils, the average offensive output for those teams last year was 789.5 runs. That second average still is higher than that of the AL Central teams he faced last year, but it's only higher by 14.75 runs.
Over a 162 game season, a difference of 14.75 runs is less than a tenth of a run per game. If Santana pitched for the Red Sox, that difference would be more significant at a quarter of a run per game. And Fenway Park would likely also cause an increase in his ERA, but park factors only hurt peripherals, not ability to win games because visiting pitchers suffer under the same park factors.
One also must ponder the affects of the Orioles and Rays losing some of their best run producers in Miguel Tejada and Delmon Young. I doubt the loss of those two players alone will affect the potency of AL East offenses all that much, however.
In reality, it appears as if pitching in the AL East would be slightly more difficult than pitching for the Twins in the AL Central. But while the AL East may hurt his peripherals, pitching for the Red Sox or Twins would significantly help his win totals. Those teams are likely to a couple of the most winningest teams of 2008, with a couple of the best offenses in baseball.