WALTHAM, Mass. — The Boston Celtics' biggest opponent right now is the training room.

The Celtics will not dress five players when they play at the Miami Heat on Wednesday night.

Coach Doc Rivers on Monday ruled out Rajon Rondo and Glen 'Big Baby' Davis after both sprained their right ankles over the weekend. Rondo was hurt in Friday's 105-94 win over Cleveland and Davis in Sunday's 86-79 loss to Orlando.

They join superstar Kevin Garnett, Brian Scalabrine and Tony Allen on the sidelines. Garnett has a sprained right knee and Allen has an injured left thumb. Scalabrine has post-concussion syndrome.

Rivers said he expects Davis and Rondo to miss at least the next two games. After Miami, Boston hosts Memphis on Friday and plays at Milwaukee on Sunday.

"Kevin will be out longer than the Milwaukee game," Rivers said. "I'm pretty sure of that. I would say Kevin, maybe at the end of the following week at the earliest."

Rivers also said he'll limit the time for Paul Pierce and Ray Allen, who each played 45 minutes on Sunday.

"Somebody else has to step up and the challenge for me is not doing what I did (Sunday) with Paul and Ray, that can't happen," Rivers said. "Obviously, that was a different circumstance because the injuries happened during the game or right before the game. It's tough to plan for but I still want to keep their minutes down, even in a time of crisis I want to keep their minutes down. We just have to find a way to win games."

Only 10 players dressed for Monday's practice, with Ray Allen and Pierce getting excused after 30 minutes.

"This is a growth period for our basketball team," Rivers said. "Clearly, we want to win the games but we have an opportunity to grow our team in this little stretch and get them closer together and get them all understanding how hard the work is going to be to win a title. In the long run, I think this might make us a better team."