Why does Rick Carlisle not play Rodrigue Beaubois?

I'm a Mavericks fan and I don't even know! Beaubois is a great player and is extremely fast. He scored 40 points against Golden State. He is also the most lethal weapon that the Mavericks had against the Spurs. But Rick Carlisle didn't play him. I've heard that Rodrigue was in the "doghouse" for something?