COLLEGE STATION -- If Justin Dunning never wanted to play football again, his coach wasn't going to take it personally.

In fact, Texas A&M's Kevin Sumlin would have understood if the defender hadn't come back to the Aggies after suffering a season-ending knee injury last August. After the third such injury in Dunning's career, Sumlin wasn't sure if he was returning to the team.

"He took some time," Sumlin said. "He started hanging around. He came back in and said, 'Coach, I want to try it again.'"

On Thursday, Dunning was suited up for the team's scrimmage at Kyle Field. After missing last season, the 6-4, 240-pound sophomore linebacker could be big piece for the Aggies after months of working to play with his teammates again.

"Every day, you could see him while we're out there on the field," A&M senior safety Armani Watts said at SEC media days.

In July, A&M defensive coordinator John Chavis said Dunning could fill the void as the team's starting nickelback, a hybrid between a linebacker and a defensive back. Senior Donovan Wilson would move over to safety, where he would join Watts at the back of the Aggies defense.

Dunning is roughly 30 to 35 pounds heavier than he was when he arrived in College Station, leading Chavis to joke that if Dunning got any bigger, he'd have to line up as a defensive lineman.

But even with the extra pounds, Chavis said Dunning has retained his speed. That could bode well for a defense that's admittedly lacked solid play in the middle of the field.

Asked why the A&M linebackers will be better this season, junior linebacker Otaro Alaka said that the depth and experience from guys like Dunning should improve the unit.

"His transition's been pretty smooth," Alaka said of Dunning. "He looks like he knows what he's doing. I think if you give him some time, he can be a really good linebacker."

During his freshman season in 2015, Dunning appeared in 11 games as a defensive back and tallied 20 tackles and one interception. Last August at the start of the preseason, Dunning was praised by Sumlin before suffering a torn ACL in his right knee on a non-contact play.

The sixth-year A&M coach said the injury couldn't have happened to a better person. Dunning tore the same ligament twice in his left knee, including in the first game of his junior season.

"Every time he's battled back, something's happened," Sumlin said.

That was part of the reason the A&M coaching staff kept Dunning out for the final two weeks of spring practice. Sumlin said that if Dunning was going to get injured again, he didn't want it to occur in late April. The A&M coach wanted to give 20-year-old the best opportunity to play football.

Dunning took the extra time to get stronger and prepare for a return to the field. The day finally arrived Thursday, when he and the Aggies practiced inside an empty stadium that will be filled with more than 100,000 fans this fall.

Last August, Dunning could have walked away from football. The Aggies were going to keep him on scholarship for the remainder of his stay at A&M.

But he hung around, until finally he decided he wanted to give it another shot. One year later, Watts, one of A&M's starting safeties, predicts Dunning will make a big impact on the defense this season.

"He's going to make some noise," Watts said.

Twitter: @Ben_Baby