Clippers rookie forward Blake Griffin is expected to make his debut in Friday's preseason game against the Trail Blazers.

The first overall pick suffered a knee injury five days before the start of training camp. He will participate in contact drills during practice on Thursday.

"I've only been out a week, but it feels like a month," Griffin told the Los Angeles Times. "Even watching practice is rough. It's worse that I'm completely dressed and I have the uniform on."

He would have practiced on Wednesday, but the Clippers have the day off.

"He's been bouncing off the walls," coach Mike Dunleavy said of Griffin. "We've been holding him back, which is driving him crazy."