"He has already adopted the nickname "Dream," something Hall of Famer Hakeem Olajuwon emphatically put in the NBA lexicon.

Given how Grizzlies rookie Hasheem Thabeet looked until the team's first two preseason games, you could understand the snickers.

Thabeet must be dreaming, right?

The No. 2 overall pick in the June draft didn't come close to dominating the rookie/free-agent showcase at Las Vegas in July. Then, the 7-3 Thabeet often wandered aimlessly through Grizzlies' training camp at Birmingham-Southern College.

First impressions hardly suggested "HasheemTheDream," as his Twitter account states. He seemed more like HasheemTheLostCause, a rookie asleep for too many stretches on the court.

But Thabeet is working to change those first impressions -- and there are some promising signs from the first 40 minutes of his NBA career.

"One time Hasheem blocked a shot and the second time he causes the guy to miss and the third time he doesn't jump. You still have to make a third effort," Griz coach Lionel Hollins said, describing Thabeet's preseason debut Tuesday against Washington. "But then he comes back and makes a couple of efforts and blocks a shot, and he gets the ball as it falls away. Those are the types of things that help you win."

Thabeet still is a project for many reasons, but no longer is he trying too hard to prove he's worthy of his draft status.

Forget being dreamy, Hollins demanded of the Tanzanian, and just be an old-fashioned deterrent at the rim.

With 11 rebounds, five blocks and countless shots altered, Thabeet has used the preseason so far to show he now understands what's expected of him: protect the rim.

"Even if I'm not going to block your shot, I'm going to intimidate you," Thabeet said. "I'm going to challenge you. I have to keep doing what I do. The coaches are always telling me, 'Don't go out there trying to do things you've never done before. Do what you know.' So I try to challenge every shot."

Thabeet's directive is simple: Take away the layup when an opposing player enters the lane. Floating away from the rim and near the free-throw line often drew the ire of Hollins and confusion from teammates during practice.

"It's great to have guys like Zach (Randolph) on the team," Thabeet said. "He tells me to show everybody I've got heart. He says if you have heart that takes care of everything else. Heart controls your body. It controls your mind.""