1. Hank Greenberg, 25 homers, 1947: After missing nearly five years for military service, Greenberg was coming off a resurgent 1946 campaign when the Detroit Tigers sold him to the Pittsburg Pirates. As recounted in The Glory of Their Times, Greenberg considered retiring until the Pirates offered to move their left field fence in, let him choose the amount he was paid– $100,000– and release him at year’s end. Greenberg is primarily remembered from 1947 for mentoring Ralph Kiner, though the 36-year-old put up stats suggesting he could have played a couple more years. Aside from a 131 OPS+, Greenberg tied for the National League lead in walks with 104 and cost the Pirates just two defensive runs.
2. Ted Williams, 29 homers, 1960: According to a piece by Glenn Stout referenced in an Out of the Park Baseball forum, Williams turned down $125,000 to pinch hit for the New York Yankees in 1961. Like Greenberg, Williams’ final season suggested he had more to offer. His .645 slugging percentage is tops, by far, among players with at least 300 plate appearances their final season. Williams’ 190 OPS+ his last year is also far and away best and, interestingly, identical to his lifetime rate. Had there been DH’s during Williams’ career, the Splendid Splinter could have played until he was 45.
3. Dave Kingman, 35 homers, 1986: Kingman has the most homers his final season of any player. In almost every other respect, though, he was historically bad in 1986. His slash was a ghastly .210/.255/.431. His -3 Wins Above Average are the worst of any player in their last year. His 126 strikeouts are second-worst. In addition, Kingman sent a live rat late in the season to my future editor Susan Fornoff, one of the first female reporters allowed in locker rooms. Not surprisingly, the Oakland A’s let him walk. Save for a brief stint the following season with the San Francisco Giants’ Triple-A club, he was done.
4. Mark McGwire, 29 homers, 2001: Big Mac’s final season is a little underrated, since he declined dramatically from what he did the preceding five years and hit below the Mendoza Line. That said, it might be the best sub-.200 season a hitter’s had, with McGwire homering once every 10.3 at-bats and offering a 105 OPS+ thanks to his power and on-base abilities. While he was an injury-riddled mess at the end of his career, he remained a threat when healthy.
5. Barry Bonds, 28 homers, 2007: That Bonds had a 1.045 OPS his final season and couldn’t get work thereafter is a testament to how cancerous of a player he became or at least was perceived. Only Williams and Shoeless Joe Jackson have also had OPS’s over one their final seasons.
6. Jermaine Dye, 27 homers, 2009: Dye peaked late, hitting 187 of his 325 homers after age 30. That said, when he declined, it may have been in a hurry. Dye was on-pace for 40 homers and a .300 batting average through the first half of the 2009 season. The Chicago White Sox declined to resign him, though, after he posted a .179/.293/.297 slash in the second half with just seven homers.
I seem to recall a team wanted to sign Kingman for ’87; can’t recall which club but they needed a big bat and Kingman was only asking $250,000 for the season, cheap! Didn’t happen, though.