Including six this season, there have been a total of 310 40+ HR seasons in baseball history, by 130 different players. The first of them was by Babe Ruth in 1920. Between then and the strike in 1994, it was accomplished 154 times. It has been done 156 times since 1995, which means it’s happened more frequently in the last eighteen seasons than the rest of baseball history.
The last season without any 40 HR hitters was 1982. The last season with only one 40 HR hitter was 1989, when Kevin Mitchell easily led the league with 47. In 1996, a record seventeen different players hit 40 or more. Between 1996 and 2006, at least nine players reached the mark each season. Since then, it has become a bit less common again, with only two players getting there in 2008, 2010, and 2011.
Of the 130 players who’ve hit 40 or more in a season, 64 of them have done it just once (though there’s a good chance some of the active one-time members will eventually have a second 40+ season). Twenty players have hit at least 40 home runs five or more times:
It is no surprise that such a list would include so many of the greatest power hitters in history. Fourteen of the twenty players have hit 500+ home runs (with Pujols and Dunn still playing) and only Ralph Kiner didn’t hit at least 400 in his career (369). If you look at the twelve players with six or more 40+ seasons, it’s ten of the top eleven home run hitters in history (only Frank Robinson is absent), plus Pujols and Dunn.
With Adam Dunn having hit 40+ home runs five times already, the 41 bombs he hit this year may not have seemed very surprising, but after the abysmal 2011 he put together, it was certainly a much higher figure than even most optimistic projections had him down for.
It was Dunn’s .159 batting average that got the most attention in 2011 (only a few late-season benchings kept him from reaching 502 plate appearances and officially qualifying his average as the worst in history), but he also hit just 11 home runs. As the 2012 regular season ended, I found myself wondering just how rare it was for a player with so few home runs one season, to hit so many the next.
Here are the fewest single-season home run totals that were followed up by 40+ the following season:
Rank
Player
Year
Team
PA
HR
10th
Adam Dunn
2011
White Sox
496
11
10th
Javy Lopez2002
Braves
385
11
10th
Chuck Klein
1928
Phillies
275
11
9th
Jim Thome
2005
Phillies
242
7
7th
Davey Johnson
1972
Orioles
436
5
7th
Jim Edmonds1999
Angels
233
5
6th
Mark McGwire
1986
Athletics
58
3
4th
Hank Greenberg
1936
Tigers
55
1
4th
Carlos Pena2006
Red Sox
37
1
1st
Harmon Killebrew
1958
Senators
33
0
1st
Cecil Fielder
1989
*DNP*
0
0
1st
Willie Mays
1953
*DNP*
0
0
Davey Johnson’s 1973 season is one of the great power explosions in baseball history. Until then, Johnson had been a fairly light-hitting second baseman, playing for Baltimore in four World Series. He’d never put up a slugging percentage of even .400 just once in seven full seasons with the Orioles. He’d hit just 66 career home runs in 3,489 at bats, a rate of 1 per every 53 AB. After the 1972 season, Johnson was traded to Atlanta, where he proceeded to hit 43, a rate of 1 per every 13 AB, more than four times greater than his career figure before then. He never hit more than 15 home runs in a season after that.
Cecil Fielder spent the 1989 season in Japan, where he hit 38 home runs for the Hanshin Tigers, while Willie Mays missed 1953 because he was serving in the U.S. Army during the Korean War. Upon his return to MLB, Fielder became one of the better power hitters of the early 90s. Upon his return to MLB, Mays become quite possibly the greatest player ever.
Most of the guys on the list didn’t play anything close to a full season. Dunn’s 496 plate appearances are 111 more than the next highest total. His 11 home runs in 2011 were the fewest ever hit over anything approaching a full season a year prior to a guy hitting 40 or more. With two more seasons at $15 million apiece remaining on Dunn’s contract, White Sox fans will have to hope the power is back to stay.