AUSTIN, Texas – Secondary coach Chris Vaughn knows he has three starters he can count on – seniors Quandre Diggs and Mykkele Thompson and junior Duke Thomas – but the depth on the back end is a work in progress.

That said, Vaughn isn't going to be shy about running walk-on players and true freshmen out onto the field if they're worthy.

Senior safety Josh Turner was expected to start at alongside Thompson but he's been suspended for at least the Aug. 30 season opener against North Texas. When asked if Turner is in the mix to be a starter, Vaughn made it clear where Turner stands.

“He's not right now,” Vaughn said. “He's getting some down-the-line reps. He's showing us that he can be accountable and doing the things he needs to do. But he's handled it well and come to work every day. He understands why he is where he is and he's going to work.”

Vaughn was impressed with walk-on Dylan Haines in the spring and he's continued to get reps with the first defense in this camp. He calls Haines a tough playmaker who is accountable and runs well, and more importantly Haines isn't practicing like he's protecting himself from possibly losing a starting job.

“I don't think he thinks that way,” Vaughn said. “He's a guy who wants to do what he can to help this football team. I think he wants to not let the team down as opposed thinking that he's back against the wall or anything like that.”

True freshman Jason Hall started taking starting reps at safety in practice this week. Though not highly ranked as a recruit, Hall had offers from Nebraska and Oklahoma in addition to Texas and is said to have absorbed the playbook quickly and has a grasp of what he's been asked to do already.

In addition to Hall, fellow freshmen Jermaine Roberts and John Bonney have also impressed Vaughn in this camp. Roberts has been working with the second team at cornerback while Bonney has worked at cornerback and as the nickel back with the second unit.

Vaughn likes that both of the youngsters have shown a willingness to compete from the start of camp.

“The one thing they do have is they understand football,” Vaughn said. “They know how to compete. They go hard.”

Both appear to be ahead of redshirt freshman Antwuan Davis, who Vaughn said has some work to do.

“The thing he has to continue to do is learn the game and understand the game,” Vaughn said. “When you don't understand the game you can't play at 4.3 (40-yard dash speed). When you understand concepts and understand what you're doing pre-snap, once the ball is snapped, then you can get to your true speed.”

While the Longhorns have another week of camp and two scrimmages to get the depth chart figured out before the first game, Vaughn made it clear what he's told the players in his meeting room.

“If you're a good player you're going to play,” Vaughn said. “The best player will play.”