The Rebels beat the Bulldogs 82-63. Henderson scored 19 points.
As Henderson is walking off the court, video from the game shows Henderson talking to his teammates in a dramatic manner as he heads to the bench with six seconds remaining.
As he passes by the Mississippi State bench, the video shows Ray mouthing something back to Henderson.
"I responded inappropriately to an Ole Miss player [Saturday] in our game,'' Ray said in a statement he texted Sunday. "I reached out to [Ole Miss] coach [Andy] Kennedy immediately to apologize and subsequently to the player too. There is no reason for a coach to ever have interaction with an opposing player, ever, regardless of the circumstances. I was more upset with our performance than the player. I was totally at fault.''
Henderson has developed a habit of getting under people's skins, often motioning to opposing fans and even mockingly performing the Gator "chomp" after beating Florida in last season's SEC tournament final.
The loss dropped the Bulldogs to 13-6 overall, 3-3 in the SEC while the Rebels moved to 5-1 in the SEC, 14-5 overall. Mississippi State beat Ole Miss 76-72 in the first meeting this season in Starkville on Jan. 11.
Ray is in his second season with the Bulldogs.