Manny Pacquiao -- 1st Post-Surgery Selfie

Manny Pacquiao says his shoulder surgery was a rousing success -- and just posted his first post-op selfie to prove it.

Pacman went under the knife in L.A. Wednesday night to repair a torn rotator cuff in his right shoulder -- an injury that he didn't properly disclose to officials before the big Mayweather fight.

Of course, Manny thanked God for the procedure ... and his wife ... and his world famous doctor ... saying, "Thank you to my Dr. Neal Ellatrache and his group for taking care of me. God is great!"

One thing we noticed in the pic ... not a single mark on his face.