Fernando Tatis Jr. can clearly do EVERYTHING on the baseball diamond -- including hitting a full split to steal a bag in a game!!

The MLB superstar showed he's got that in his bag of tricks during the Padres' tilt with the Rockies on Wednesday ... twisting like a gymnast to make sure he was safe at second.

The play was seriously awesome ... the 22-year-old got on first base in the second inning via a single to center and took off for 2nd just moments later.