ATLANTA -- If the Heat are to beat the Hawks in Game 7 on Sunday, they will have to do it without Jermaine O'Neal.

The veteran big man will miss his second straight game with a concussion, Heat coach Erik Spoelstra said. O'Neal suffered a concussion in Game 5. He was averaging 16 points per game in the series. Joel Anthony started in place of O'Neal in Game 6 and is expected to start Game 7.

"(O'Neal) practiced yesterday and he feels better today, but our medical people do not feel he is ready," Spoelstra said.

Hawks center Al Horford will start after missing Game 6 with a sprained ankle, and guard Marvin Williams will dress and is available, according to coach Mike Woodson. Williams has been battling a wrist injury in the series and played just five minutes in Game 6.

"We will have to keep an eye on both those guys and just see how they are and how much they can go," Woodson said.

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