The Celtics are cautiously optimistic that guard Tony Allen will be ready once training camp begins.

Allen missed the final 48 games of last season due to a torn anterior cruciate ligament in his left knee. Celtics executive director of basketball operations Danny Ainge said today that Allen was recently cleared to play, was working out on the floor today at the team's facilities in Waltham and is expected to be ready for the upcoming training camp. The 6-foot-4, 213-pounder averaged 11.5 points, 3.8 rebounds, 1.7 assists and 1.48 steals in 33 games last season.

"(Allen's) been cleared to play and do everything on the court," said Ainge, in a phone interview. "We've been totally conservative. It takes time to get the confidence back. You worry about significant injuries, but I'm optimistic for Tony."