Four pairs of teammates hit at least 45 home runs in the same season. One pair did it twice.

Teammates who hit at least 45 home runs in the same season:
1961 Roger Maris (61 home runs) and Mickey Mantle (54), Yankees
1927 Babe Ruth (60) and Lou Gehrig (47), Yankees
1931 Babe Ruth and Lou Gehrig (46), Yankees
2001 Alex Rodriguez (52) and Rafael Palmeiro (47), Texas
2005 David Ortiz (47) and Manny Ramirez (45), Boston

? 2018 Giancarlo Stanton and Aaron Judge, Yankees? Stanton is joining the Yankees in 2018. In 2017: Stanton hit 59 for the Marlins, Judge 52 for the Yankees. Maris and Mantle in 1962 are the only other teammates to hit 50 homers the previous season and they, of course, did it as teammates in 1961.

Roger Maris loses 1960 Home Run race to Mickey Mantle 40-39. Thursday, June 1, 2017

Why look at Roger Maris in 1960? Because it provides a base of comparison to his record setting season of 1961, which, of course, had 5% more games and pitching diluted significantly.

Mickey Mantle was the Home Run king of baseball by 1960, winning his fourth American League (AL) championship in six years and his second Home Run race in three years. In 1958 Mantle had edged Cleveland's Rocky Colavito 42-41.

1958 AL Home Run race. Who "led the league in hitting" ... home runs? Thursday, March 31, 2016
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Mantle & Maris still only teammates to hit 50 HR. Tuesday, June 28, 2011

In a sense, Ruth and Gehrig come the closest to being teammates hitting 50 in the same season.  Then there are Albert Belleand Jim Thome with Cleveland.  Belle hit 50 in 1995 and teammate Thome hit 25.  In 2002 Thome hit 52 but Belle left Cleveland after the 1996 season and retired after 2000.

I'm not even sure how many other pairs of 50 homer batters were ever teammates even on different teams.  The 2011 Yankees have Alex Rodriguez (Texas 57, 52 and Yankees 54) and Andrew Jones (Atlanta 51).  Mantle played with Johnny Mize (NY Giants 51) 1951-1953 but Mantle did not hit 50 until 1956 (52).  Pittsburgh 1947: Greenberg (Detroit 58) and Kiner who hit 51 that season.  There may be others but you get the idea.

That makes the 1961 Yankee achievements all the more special.
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