Pleading his case happens 1000 times in a game, and the ref had already called the foul, so there's no effect there.About the Flagg "foul", it wasn't "over the back". Flagg was going for the rebound, #13 for Houston was holding Flagg at the hips. Holding is not blocking out. When the whistle blew, #13 for Houston went straight to the Ref to plead his case because of it. Watch at 20:13
I agree that a foul should not have been called there. But Duke choked the game away anyway. One could argue that Flagg shouldn't have fought so hard for that rebound, risking a foul, in a one-point game.