PROVO — Bronco Mendenhall learned a lesson a year ago and he's carefully monitoring physical play in the Cougar fall football camp because of it.

Last August, in a matter of days of Mendenhall's opening 2005 camp, he had walking wounded limping around the sidelines unable to practice. For a team battling depth issues, especially in the secondary, it cast a shadow on two-a-days.

In spring 2006, injuries and surgeries limited scrimmages due to lack of bodies on the offensive and defensive line.

That's why his staff drew in collective breaths when offensive tackle Ray Feinga stayed down on the turf after BYU's first running play in the initial 11-on-11 drills in full pads on Thursday. All the men in whistles demanded nobody hit the ground and keep their feet.

Said Mendenhall, "After last year, my perspective is different, so I find myself weighing the tradeoffs of what we'll do and what tempo in order to get ready to play a game."

Fortunately for Feinga, who underwent shoulder surgery after the Las Vegas Bowl, he was not seriously injured, only bruised and sat out the rest of the morning session.

With outside junior linebacker Markell Staffieri out with a hamstring injury suffered Tuesday when he tried to hurdle a pile of players, Mendenhall said both Feinga and Staffieri should be ready for the Arizona game. But he's going to walk a tight wire with game preparation and the need for knocking heads around on a daily basis.

Both starting corners, Justin Robinson and Kayle Buchanan, have missed practices. And running back Fui Vakapuna sat out Thursday after receiving a minor injury with his physical play.

Otherwise, Mendenhall hasn't changed his practice format at all. In pads, one session a day will center on the running game and when in shells (helmets and shoulder pads), the focus will be on drop-back passing, pass rushing and the aerial game.

Thursday's practice lacked the echo of colliding pads and helmets, but it was by design as many positions on defense remain open.

"Our execution is getting better. It doesn't sound right, but we're not asking it to sound right at this point, we'll know more on Saturday when we scrimmage," Mendenhall said.

"The best benefit right now is the protection and health part of it. When a guy goes down, to have padding and protection on his legs, is important."

Mendenhall made one personnel shift Thursday, meeting with former Brighton all-stater Mike Hague in the morning to inform him he'll shift from safety to running back and H-back receiver.