I detected this trend -- which began with Rodriguez's age-24 season in 2000, his last with the Mariners, continued through his three seasons in Texas and concluded with his first season as a Yankee in 2004 -- in several park-adjusted, total-offense rate stats, including Baseball Prospectus's Equivalent Average (EqA), Baseball-Reference's adjusted OPS (OPS+), and Bill James' Offensive Winning Percentage (OWP). Consider the following progression from 2000 to 2004, with Rodriguez's three Texas seasons in bold:
I could have listed other stats that exhibit the same trend, both adjusted and non-adjusted (WARP, Runs Created, Runs Created Against Average, Runs Created Per Game, unadjusted OPS, Gross Production Average, etc.), but there was no need. The trend was real and four years running.
That analysis was untainted by any knowledge or suspicion of Rodriguez's drug use while with the Rangers. Just as I have now done four years hence, I wrote off the apparent surge in Rodriguez's numbers while in Texas as park-driven while digging beneath those gaudy counting stats to reveal a modest decline in his overall production during his three years in Texas.
Since joining the Yankees, Rodriguez has enjoyed the two best seasons of his career, both of which supposedly came without the aid of performance-enhancing drugs. Consider how his MVP seasons of 2005 and 2007 compare with the five seasons listed above:
Put this all together and it's clear that, if he is indeed telling the truth about his drug use being limited to his three years in Texas, the only noticeable benefit that Rodriguez derived from his experimentations with banned substances was his ability to play 485 of the Rangers' 486 games during his three years with the club. That's no small thing. There are some who believe that the most undervalued statistic in baseball is games played. It's irrefutable that Rodriguez's ability to take the field every day as a Ranger enabled him to put up the remarkable counting stats he compiled in a Texas uniform, chief among them his 57 home runs in 2002. Still, there's no evidence that the drugs made him any more powerful, and significant evidence that his rate of production actually declined during what he claims were his doping years.
Rather, it was the ballpark, not the drugs, that seems to have been the key to Rodriguez's statistical surge (34 of his 57 homers in 2002 came in Arlington, where he homered once every 10.6 PA vs. once every 15.7 PA on the road in '02). Whether or not that's enough to convince anyone, myself included, that his statistics remain "untainted" is, unfortunately, another matter entirely and one far less likely to be settled in Rodriguez's favor.
Cliff Corcoran is a frequent contributor to SI.com.