Rondo told reporters he was not fit to face the Celtics later Wednesday in Game 5 of the two sides' Eastern Conference battle, which is finely balanced at 2-2.

"I'm not playing," Rondo said. "The slightest fall on the floor might further damage it. ... My thumb is the same as it was last week. I think I'm Wolverine but it hasn't healed that quickly yet."

Rondo excelled for the Bulls to help them take a 2-0 series lead.

But he missed Games 3 and 4 with the injury as Boston fought back to level the series.

Rondo, who averaged 7.8 points, 6.7 assists and 5.1 rebounds in 69 games this season, said recovering in time for Game 5 had always been unlikely.

But he did not rule himself out of Friday's Game 6.

"I got an X-ray (Tuesday). The thumb is still the same. It's still broke," Rondo said Wednesday.

"I knew last week it wasn't going to be fixed in a week. My finger is broken."