I heard from some people who were there that the "injury" last week was a mysterious one that appeared only after he was benched by the head coach for the 2nd half of the game after committing a personal foul.
After halftime, he was sitting on the bench when the coach told him that only players who were going to play could sit on the bench and that, since he was not going to play, he would have to go to another area on the sideline. At that point, he got up from the bench, took off his pads, and told the trainer that his shoulder was sore and that he needed to have ice applied to it.