"And that is one of the biggest bush league things I've ever seen! That is terrible!" ESPN announcer Mike Tirico said.
The 22-year-old took his jersey off and was escorted off the court by team staff and teammate Ron Artest.
In the final seconds of Game 2, Artest inexplicably clotheslined Barea and was suspended for Game 3.
Bynum's ejection came shortly after Lamar Odom was tossed for a flagrant foul against Dirk Nowitzki.The Mavericks went on to win 122-86, eliminating the defending champions.