Tyler Hansbrough entered the NBA with much to prove after the Pacers took him in the first round of the 2009 draft.

The 6-foot-9, 250-pound power forward was dominant at North Carolina, but he knew some critics questioned whether he had the size or the athletic ability to make it in the NBA.

Medical issues prevented him from showing much in Indiana.

He missed time early in the season with a shin injury. He returned and showed promise before an inner ear infection caused dizziness and made him sensitive to light. He played in only 29 games.

Now, he has been cleared for contact and is been practicing with the Pacers during training camp. He was his usual aggressive self during a scrimmage on Tuesday, throwing his body around, clogging passing lanes and even knocking a driving Danny Granger to the floor.

"I'm feeling great," he said. "I've made a lot of progress. I feel very optimistic."

Hansbrough averaged 8.5 points and 4.8 rebounds last season. He scored a career-high 21 points last Dec. 11 against New Jersey, and got his first career start on Jan. 13 against Phoenix.

He didn't play again after Jan. 16. The former AP college player of the year hadn't dealt with a serious injury in his career, so sitting out was foreign to him.

"It was frustrating," he said. "I wasn't happy with my situation, and there was nothing I could do about it, so I was just trying to focus on getting healthy."

He spent much of the summer recovering back in North Carolina. While coach Jim O'Brien said Hansbrough showed up to camp in "remarkable shape," Hansbrough disagreed.

"I feel like I'm not in the best shape in my life, but I'm not in the worst," he said. "I feel like I'm in good shape."

Hansbrough said the Pacers will bring him along slowly. O'Brien is being careful about putting too much on Hansbrough.

"I expect him to be healthy, which he is," he said. "I couldn't have been happier two Junes ago, drafting him. He's got a tremendous passion and intensity for the game, but I also know there has to be some rust by him virtually missing all of last year."

Hansbrough said he gained experience during his 510 minutes last season, but needs to improve his defense.

Hansbrough spent last year learning from Troy Murphy, a veteran power forward who was traded to New Jersey. Murphy's departure opens a door for Hansbrough. He'll compete with Josh McRoberts, Solomon Jones and Jeff Foster for the starting job.

"I think Troy was a good guy to learn from while I was healthy," he said. "It is a good opportunity to kind of have a possible starting job, but more important, just getting out there and playing like I used to."

O'Brien said for Hansbrough to increase his minutes, he'll have to adjust his mindset.

"In college, he was a scorer and an attacker," he said. "He has to develop his game where he's also a facilitator — when he's not a a position to score, he has to be effective in his ability to pass the ball to his teammates."

O'Brien is convinced Hansbrough will be a good NBA player.

"By the end of this year, we'll know what we have in Tyler, and I believe we will be pleased with what we have," he said.