By TMZ Sports

Eight division world champion Manny Pacquiao says his right 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 Floyd Mayweather Jr. fight last Saturday night at the MGM Grand in Las Vegas.

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!"