If Aaron Judge seems to be moving just a tiny bit slower at Tuesday night's All-Star Game ... now ya know why!!!
The New York Yankees superstar was spotted partying in L.A. the day before the mid-summer classic on Monday ... hitting the Fanatics ASG bash in downtown -- and rubbin' elbows with Travis Scottand some NBA superstars while there!!
TMZ Sports has some pics from the festivities -- and you can see Judge, rockin' a custom blazer with a white shirt underneath, seemed to be enjoying himself big time as he chatted with the celebs at the venue.