Before we begin our look at first basemen I want to acknowledge Rob Neyer's comments on the catcher's piece and jump on the bandwagon predicting Jorge Posada's batting average will fall below .300 next season.
Continuing our series here are the 30 first basemen ranked by at-bats and then sorted by OPS, but before I list them let me point out that players like David Ortiz and Travis Hafner are listed as designated hitters rather than first basemen, none the less here are the 30; Pena, Teixeira, Fielder, Pujols, Howard, Helton, Loney, Stairs, Lee, Berkman,Young, Hatteberg, Gonzalez, Youkilis, Garko, Konerko, Kotchman, Jackson, Morneau, LaRoche, Wilkerson, Millar, Delgado, Jacobs, Johnson, Casey, Klesko, Overbay, Garciaparra, and Sexson.

Carlos Pena set the trail for first basemen, posting a 1.037 slugging - the average first baseman's OPS figured out to be .824, and less surprisingly than we found with catchers yesterday about two-thirds of first basemen topped average. Pena, Mark Teixeira , and Prince Fielder were the only ones to go over 1.000, but Albert Pujols, Ryan Howard, and Todd Helton were .100 points over with James Loney, Matt Stairs, and Derrek Lee barely missing. Lance Berkman finished within .070 points, Dmitri Young, Scott Hatteberg, and Adrian Gonzalez were at least .020 points above average.
It shouldn't be much of a surprise that Pena won the American League Comeback Player of the Year, and the award is ironic that even the Rays had cut Pena before reserve first baseman Greg Norton hurt his knee - causing the team to re-sign Pena, less than 12 months later he recently inked a three year 24 million dollar deal - only in baseball. The hot question is whether Pena's season was a fluke; hit walk rates shot up from a career average of 12.5% to 17.4%, his strikeout rates remained within 0.05% of career norms and his expected BABIP was .005 points lower than his performed BABIP. Minus his HR/FB rates going from a 20% average to 29.1% - which suggests some luck, and perhaps a little luck in walks Pena likely won't bomb, but will likely regress in batting average and homeruns.
Only three players fell .100 points below the average and Lyle Overbay's poor season can be chalked up to injuries, Nomar Garciaparra played in the same amount of games as he did in 2006 when he posted a 120 OPS+ needless to say his 78 OPS+ along with Loney breaking out contributed to Nomar shifting to third base where he'll block Andy LaRoche until Ned Colletti and crew decide enough is enough.
Then you have Richie Sexson, in 1998 he played in more than a handful of games and hit well enough for a slugging percentage of .592, since then he's finished with a SLG% higher than .500 all but twice - once in 2000, .499 thanks to a surge after being traded from Cleveland to Milwaukee, and last year hitting .399. 32 year olds usually don't break down like that and to say Sexson was unlucky is like saying you can't see air, his xBABIP was .270, his real BABIP a measly .217. No surprise that Sexson's HR/FB rates went down upon arriving at Safeco. I'm willing to predict that Sexson's OPS will top .750 next year with a very real chance of hitting .800.
Finally as another breakout or bounce back how about Adam LaRoche? His splits amuse me if nothing else, hitting .881 at home and .721 on the road but he tore it up in the second half raising his Ops from .763 to .854, his BABIP and xBABIP match up almost perfectly, and with the exception of his HR/FB rates nothing looks outrageous and even those numbers were more in line with his career numbers.