Boston Celtics coach Doc Rivers says Tony Allen might not be back from an injury to guard Los Angeles Lakers star Kobe Bryant when the NBA finals begin Thursday night.

"It doesn't look good," Rivers said after practice on Monday. "He couldn't get through even the walkthrough portion." Allen had some success against Bryant in the regular season, but the Celtics guard injured his Achilles tendon in a post-practice pickup game during the Eastern Conference finals and hasn't played since.