BOSTON - It's a good thing for the Boston Celtics that the NBA rescinded Kendrick Perkins' technical foul and nixed his suspension.

Perkins may be the only big man they have left to guard Orlando Magic center Dwight Howard.

Perkins was ejected from Boston's 113-92 loss to Orlando in Game 5 of the Eastern Conference finals on Wednesday night after picking up two technicals in the first half. The league rescinded one Thursday, clearing Perkins to play in Game 6 on Friday night when Boston tries for the third time to eliminate the Magic and advance to the NBA Finals.

"We know what we haven't done, and what we need to do," Celtics coach Doc Rivers said Thursday. "I think we'll be ready to do it tomorrow night."

Even with Perkins, the Celtics will be shorthanded trying to slow Howard, who has averaged 26 points and 13 rebounds in the last two games as the Magic twice avoided elimination.

Backup Glen "Big Baby" Davis has a concussion. He blacked out on the court from Howard's inadvertent elbow to his face in Game 5. Former Simon Gratz High star Rasheed Wallace tweaked his back in the game and couldn't even sit to watch film Thursday.

Rivers said both are game-time decisions. Reserve Marquis Daniels also suffered a concussion, and he has been all but ruled out for Friday night's game.

"Our mentality is: We just have to lace them up and go play," Rivers said. "We have a lot of bumps and bruises right now, but we'll be OK."

The Celtics need a victory Friday night to avoid a trip back to Orlando for a seventh game, where a Magic victory would make them the first team in NBA history to come back from a three-games-to-none deficit in a best-of-seven playoff series. Former St. Joseph's and Chester standout Jameer Nelson scored 24 points in Game 5.

"I didn't like being in a 3-0 hole, but it's still doable. I don't think we've had a lack of belief," Orlando coach Stan Van Gundy said.