Frank Thomas and
Jeff Bagwell!
Having kind of come of age as a baseball fan in the 1990s, it's almost impossible for me to believe that
The Big Hurt and Bags both turn 41 years old today.
I would like to suggest, first of all, that, even without regard to simultaneity and such freak coincidences, you'd have a hard time finding two truly great ballplayers who are more similar to each other than Bagwell and Thomas are. Having played parts of 34 combined seasons, they're separated by 202 at-bats, 23 runs, 154 hits, 7 doubles (!), 20 triples, 72 home runs, 175 RBI, 4 strikeouts (!!), 4 points of batting average, 11 points of OBP, and 15 points of SLG. (And a ton of stolen bases and walks, but still.) Bill James' Similarity Scores, for what they're worth (which isn't much), lists them as each other's #1 comp.

But then of course there are those coincidences. Born on the exact same day in 1968, both drafted in 1989. Both had their first full seasons in 1991. Both had enormous offensive years and won their league's MVP award in the strike-shortened season of 1994. Both were 37 year old non-factors in their last years with the teams they had spent their entire careers with in 2005, when those two teams met in the World Series, the first for both players (Thomas didn't play but got himself a ring, while Bagwell went 1-for-8).
Differences, too, of course--Frank was huge and intimidating while Bagwell seemed a little small for the position; Bagwell reputedly played great defense, while Frank was a born DH; Frank was a first-round pick and instant star, while Bagwell was a fourth-round pick who the Red Sox traded for 22 innings of Larry Andersen; and so forth. But the similarities are more interesting, and quite a bit more numerous.
Thomas is apparently
holding out for an offer until the All-Star break, but I think we can assume that his significant contributions to the equation here are pretty well over with.
So who do you suppose was better? Here are a bunch of different ways to look at it:
OPS+: 156 to 149, Thomas. Frank was a better hitter, and it's kind of surprising that it ended up as close as that. Thomas was a legendary, Stan Musial-type hitter for the first eight or so years of his career, but then suddenly settled into being a more typical low-average, high-walk slugger like Killebrew. Bagwell was much more steady, though part of that is an illusion caused by a move from a

n extreme pitcher's park to an extreme hitter's park right around the time he started to decline.
WARP3: 105.3 to 97.2, Thomas. Baseball Prospectus' wins above replacement player stat has Thomas ahead by a deceptively comfortable margin. 8 wins above replacement equals one excellent year; Bagwell's WARP3 was exactly 8.1 in 1999, for instance, when he played all 162 and hit .304/.454/.591. A big part of that boost comes from Thomas' longevity, though; per 700 plate appearances, Thomas was worth 7.32 wins above replacement, Bagwell 7.21.
Fielding: Bagwell did it and Thomas didn't. This is theoretically accounted for in WARP3 -- Bagwell gets 205 career fielding runs above replacement and 66 career fielding runs above average, while Thomas is 26 and 87 below -- but I'm not convinced that it's covered enough. For instance, UZR is available only for Bagwell's decline years (2002 to 2005, years in which BP's system says he was pretty much exactly average in the field), but still says he was worth 5.7 runs above average in 2003 and 5.4 in 2004. It seems safe to assume that he would've shown up as being worth quite a bit more than that during his twenties. Also, in Tom Tippett's Diamond Mind Baseball simulation engine's "all-time greatest players" disk, Bagwell was rated "average" and Thomas "poor" -- a difference of about 20 runs over the course of a season.
Baserunning: Bagwell stole 202 bases at a respectable 72% clip and was known as a very smart, if not very fast, baserunner; Big Frank was a big slug, with 32 steals in 55 attempts and

that special ability to go from first to third on a triple. We can assume that Bagwell was worth a handful of runs a season over Frank, and that measures like WARP and WAR only capture a portion of that value (the part that comes from stolen bases).
Bill James: In his
New Historical Baseball Abstract, published in 2001, James ranked Bagwell the #4 first baseman of all time, and Thomas #10. In the comment to Thomas, he briefly noted the comparison, but simply said that Bagwell was a better all-around player. Of course, Thomas at that time had two more brilliant offensive seasons, two more brilliant partial seasons and one more very good full season to go, while Bagwell had two more good years and kind of skidded to the finish. Also, James' comment about Bagwell at #4 was, in its entirety: "Pass." Anybody ever figure out what the hell that was all about?
Other subjective measures: Thomas went to five All-Star games, starting two; Bagwell went to four and started two. Thomas won 2 MVPs and finished in the top 5 four other times; Bagwell had just the one MVP and two more top-fives. Thomas wins Silver Sluggers, too, four to three, though two of Thomas' were at DH rather than 1B, so that's not a fair fight. Bagwell wins in Black Ink Score (another James toy measuring how many times the player led the league in big-name categories like HR, RBI, etc.), 24 to 21, but Thomas led the league many, many more times in things like OPS, OPS+, Runs Created, and so forth. Bagwell won a Gold Glove, while Thomas appeared to actually use a glove made of gold, or perhaps a harder metal, when he was asked to play in the field.
Peak Value: From 1990-1997, Thomas hit .330/.452/.600, good for a 182 OPS+. Bagwell, meanwhile, had an OPS+ as high as 180 in only one
single season, his MVP year of 1994. From 1993-2000, Bagwell did hit .311/.428/.583, 164 OPS+. Awfully impressive, but I'm not entirely convinced you can find me a right-handed hitter since Rogers Hornsby who has put up an eight-season hitting stretch like Frank's.
So who wins? I went into this sure I was going to pick Frank, but having gone though it, I'm on the fence. I thought of Frank's offensive advantage as being bigger than it really is. I tend to be a peak-value guy--give me Mantle over Mays, for instance--but I'm no longer convinced that Thomas' peak is so much bigger than Bagwell's that it cancels out Bags' huge advantage in the field and on the bases.
So that's it:
I'm going Bagwell. But it's ridiculously close, and I'm firmly convinced that they both deserve to be shoo-ins for the Hall.
What do you think?