FLOWERY BRANCH, Ga. -- Atlanta Falcons defensive end Osi Umenyiora is embracing change. For the first time in his illustrious career, Umenyiora is getting ready for a specialty role -- a position called "DPR," which is short for designated pass rusher.

"Whatever they ask me to do, I really don't have much to say about that,"Umenyiora said. "I'm here and I'm working my butt off. I just want to help this team win."

Meanwhile, offensive lineman Mike Johnson hopes he can just make the roster and will settle for that old-fashioned term -- reserve.

It was only last season that he won the battle for the starting right tackle but then suffered a season-ending ankle injury against the Cincinnati Bengals. Now, he's trying to find a spot as a reserve.

"I'm just trying to battle in this good group for a spot," said Johnson, who was a third-round pick in 2010. "We have a lot of guys who've played a lot of good football. It's going to be tough to make the team."

Another tackle, rookie first round pick Jake Matthews, said he picked up some lessons from Houston's great defensive lineman, J.J. Watt, when the Falcons worked out at the Texans' facility Wednesday and Thursday.

"He's a helluva player," Matthews said. "That was something that I needed because I want to go up against the best players so that I can be the best player that I can be. He was going to show me just how tough it can be in the league, so that was good."

Matthews, the sixth player selected in the NFL draft, has now faced Tennessee's Derrick Morgan, Miami's Cameron Wake, Houston's Watt and Houston rookie outside linebacker Jadeveon Clowney.

"I had him a couple of times when we were working on stunts," Matthews said.

Cornerback Desmond Trufant had a strong two days of practice against the Texans.

"I'm playing with a lot of confidence," Trufant said. "I'm just working on the little things. I'm expecting big things this year."

Offensive lineman Gabe Carimi (ankle) is expected to miss a few more days of practice. He started working out with the trainers and is doing agility drills.

Running back Steven Jackson is still recovering from a left hamstring injury.