Ken Griffey Jr., 56, 1997 and '98
By 1997, "The Kid" had already topped 40 homers three times, with a high of 49 in 1996. He started the 1997 season by going deep in his first two plate appearances against and he hit had a three-homer game on April 25 against the Blue Jays. Through May, he had 24 in the Mariners' 54 games, a 72-homer pace, but added just eight over the next 50 games. A productive August that included a seven-homers-in-10-games spurt pushed him to 44 by month's end, and he added six more in the first six games of September. Even with a comparatively disappointing six homers across his final 18 games, his 56 for the season still ranked as the majors’ highest total in the AL since Maris.
Griffey looked as though he might surpass that total the following year. He hit 11 in April, and by June 11 he had 26, a 64-homer pace. He reached the All-Star break with 35 in 88 games, compared to 30 in 84 games the year before. A drought of just two homers in 27 games put him in the rearview mirror of Mark McGwire and Sammy Sosa, whose chase of Maris's record came to dominate the sports world. Griffey looked like he might get to 61 as well when he hit two homers on Sept. 22 against the A's, giving him 55 with six games to play, but he added just one more. Still, his 56 were enough to lead the AL, though it was lost amid the Big Mac-Slammin' Sammy mania.