Peter Gammons' current ESPN.COM column discusses Carlos Beltran and how his skills have put him in an elite category among center fielders.
Gammons' criterion for Beltran's exalted status is his 2004 OPS (on-base percentage plus slugging percentage). Beltran posted a .915 OPS last season in his combined AL and NL tenure, his all-time best by a wide margin. While a fine figure, however, this total would not have ranked near the top five in either league had he played a full season in one city.
Beltran's career OPS is .843. While he has improved over the years as an offensive player, especially in his strike zone judgement, he has also been quite inconsistent, batting .306 to .273 to .307 to .258 (!) over the last four years, and is moving into a ballpark--Shea Stadium--that will almost certainly strongly decrease his offensive production. Quite honestly, Beltran was never a premium player before 2004, and doing what he did last year, at age 27, is much less impressive than doing it at age 25.
Compare Carlos Beltran, then, to another contemporary center fielder who is ONE DAY older than Beltran. This center fielder has an career .837 OPS, having played most of his career in a ballpark that has significantly decreased his offensive production. This player is also an inconsistent hitter for average but has better strike zone judgement and has already hit more than 30 home runs five times in his career.
He is also quite possibly the best defensive center fielder in the history of baseball. His name is Andruw Jones.