Oklahoma offensive tackle Chris Messner was just catching his breath when he was walking toward the locker room Monday. It was almost shocking how quick he was able to recover.

If carrying around 280 pounds on a 6-foot-6 frame wasn’t enough of a burden, consider what it’s like being a Sooner offensive lineman this spring.

There’s only been seven who have gone through every practice.

That would be great depth if those were the amount of players getting practice snaps at tight end or fullback.

But you need five at all times on the offensive line. That’s why Messner, and the rest of the unit, is finding rest hard to come by.

“We’ve all got plenty to do,” Messner said.

Messner, a left tackle who started the final seven games last season, is the only regular starter going through drills this spring.

Four seniors from last season’s team are gone, and three more — Jon Cooper, J.D. Quinn and Ben Barresi — are recovering from injuries.

The numbers are thin, but the lineman who are out there are getting all the work they can handle.

Messner, guards Sherrone Moore and Duke Robinson, center Chad Roark, and tackle Branndon Braxton were the starters for last Saturday’s second scrimmage of the spring.

Brian Simmons, a converted defensive lineman, alternates at guard, and Cameron Schacht is playing at guard and center.

The Sooners ran through over 60 plays and just about all of the offensive linemen played around 50.

“The guys are working hard,” offensive line coach James Patton said. “They are doing a good job. Their effort’s good. Again, they’re going 60 or 70 plays, but that’s part of being a lineman. Those guys take pride in that.”

The lack of numbers is one of the reasons OU’s defense seems to have the upper hand in team workouts.

The Sooners’ defensive line is loaded with talent and overflowing with depth.