Rockets-Celtics game short a referee after official hurts back

BOSTON -- The Rockets-Celtics game Thursday night featured only two on-court officials.

Third referee Mark Lindsay hurt his back during pregame warm-ups before the national TV broadcast, according to the Celtics, leaving only referees Tony Brothers and Gediminas Petraitis to call the game.

The NBA typically sends alternate referees to playoff games but not regular-season matchups.

The NBA began utilizing three game officials permanently during the 1988-89 season.