LOS ANGELES -- How does Pete Alonso get himself pumped up for the Home Run Derby? He pumps iron, apparently.

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The Mets posted a short video shortly before Alonso took the field for his first-round showdown against Ronald Acuña Jr. of the Braves in which the two-time defending Derby champ was lifting weights -- in full uniform -- in a Dodger Stadium workout room Monday.

“Man on a Mission,” read the tweet.

"That's not really heavy weights; it was just more me getting activated," Alonso said after he lost to Julio Rodríguez in the semifinals, falling short in his bid to win three Home Run Derbies in a row. "I just wanted to get everything kind of firing the right way, get the body warmed up. That's typical for pregame and stuff like that."

When someone said he looked serious, the slugger replied: "If I'm going to compete, I'm going to compete to win."

Alonso’s pregame routine worked for the first round: He belted 20 homers to advance to the semifinals for a third straight Derby.