Devin Haney couldn't wait 'til Saturday to put his hands on Ryan Garcia ... 'cause the undefeated boxer shoved his opponent in the face during a heated showdown at the Empire State Building.
Haney shared the footage on his Instagram ... showing him trash-talking back and forth with a shirtless Garcia at their face-off for the April 20 fight at the Barclays Center.
Garcia (24-1) was clearly fired up ... calling Haney a "bitch" several times before Devin lost his cool and shoved Ryan hard in the face.
The push caused Garcia to stumble backward .