Major League hitters clubbed 5,392 home runs heading into Sunday's action, a pace that would surpass the second-most productive season in history when 5,528 long balls were hit in 1999.
Hitters will likely finish the season with the highest home run rate in history. They are hitting a home run in 3.06 percent of their plate appearances. Never before has the three-percent mark been cleared.
The all-time mark for home runs in a season came in 2000 (5,693).
Just two years ago, the home run rate was just 2.28 percent.