ABC
Steve Kerr was not happy when the Cleveland Cavaliers started to make a run in the second half of Game 1, destroying a dry-erase board during a timeout.
The Warriors had outplayed the Cavaliers for most of the night, building a 14-point lead. However, the Cavs cut into the lead in the third period, eventually taking a 1-point lead.
Shortly before the lead completely evaporated, Kerr went off on his play-design board, destroying it with one punch.