Arizona Diamondbacks star J.D. Martinez had a day for the ages on September 4.

The outfielder blasted four home runs in a single game to power the D-Backs to a 13-0 victory over the Los Angeles Dodgers.

Martinez became the 18th player (and the very first Diamondback) in MLB history to have four homers in one game. He joined Cincinnati Reds second baseman Scooter Gennett as the second player to do it in the 2017 season.

Martinez has been a powerful force for Arizona since his acquisition from the Detroit Tigers. This historic game gave Martinez 34 home runs for the season, and his fifth over a stretch of two games.

And based on how hard he goes in the gym, it’s no wonder he hit this milestone.

Here are five ways Martinez trains to demolish on the diamond.