Celtics center Shaquille O'Neal is active for Saturday night's Game 3 against the Heat in Boston.

"He's a go," coach Doc Rivers said less than an hour before tip-off.

"I have no idea, with him it will be the eye test," Rivers added about the center's minutes.

O'Neal will come off the bench. When asked why Boston wouldn't immediately insert O'Neal into the starting lineup, Rivers cited the veteran's lack of game action.

"I just think that's tough. There are a lot of defensive changes you have to make as well," Rivers explained.

The Celtics expect conditioning to be the biggest issue for O'Neal and Rivers said that offensively his impact will be felt immediately.

O'Neal has logged only 5 1/2 minutes since Feb. 1 because of a lingering calf injury.

In other Boston injury news, Rivers said point guard Rajon Rondo is "good" and that the team is good health-wise other than O'Neal.