PORTLAND, Ore. — Trail Blazers center Greg Oden will sit out Wednesday night's game against the Memphis Grizzlies because of a bone chip in his left knee.

Oden was hurt in a collision during a game at Golden State last Thursday. He was unable to play in the All-Star weekend's rookie challenge.

The 7-foot center is listed as day-to-day. Team doctors are expected to evaluate his knee later Wednesday.

Oden, the top pick in the 2007 draft, sat out all of last season after microfracture surgery on his right knee. He missed six games at the start of this season with a foot injury.