It's been a frustrating training camp for DE Trent Murphy. His time on the field has been a series of fits and starts due to a groin injury that has resurfaced again. Murphy, who missed time earlier in camp with the groin injury, as well as the first preseason game, aggravated the injury when he returned to the practice field on Monday.

He missed Tuesday's practice and head coach Sean McDermott confirmed he'll miss today's session as well.

"We're just going to take it one day at a time," McDermott said. "It's just something that's kind of nagging him right now."

Defensive coordinator Leslie Frazier has already stated that Murphy's availability for Friday's preseason game is in question.

When asked whether it might be best to shut Murphy down until the week before the season opener, McDermott didn't rule that out as an option.

"We're trying to figure it out honestly," said McDermott. "It's not a 'want to' issue at all. We've had a couple of groin injuries this camp, all a little bit different. We've just got to find the right formula (for him) right now and we're working hard at it."

McDermott keeping QB rotation for Cleveland close to vest

Buffalo's second preseason game is just two days away, and while the quarterbacks have been informed as to what the rotation will be against the Browns on Friday night, McDermott is not making that rotation public.

"We've got a plan. We'll just wait and see. The guys are all going to play," he said. "They will rotate in there all of them and we expect them to play well. I have addressed it with the players this morning. They know the plan."

There was a deviation in the rotation of quarterbacks in the final week of training camp. Josh Allen has practiced the last two days with the second unit, while either Nate Peterman or AJ McCarron rotated in with the third unit. The other QB was with the starting unit.

McDermott was asked what Allen's time with the second unit signifies.

"Any time you can get extended time the reps are valuable for any player let alone a young player," he said. "It also gives us a chance to evaluate him with some different people around him, particularly the people up front on the offensive line and the weapons he would have at his disposal with that group."

The Bills head coach was asked if Allen could see time with the starting unit at any point on Friday night. All McDermott would say is that it's a consideration that could become a reality, but it doesn't sound like it's part of the plan for Friday.

"We'll see. That is one thing we are considering," he said. "We want to get through this game and see how it goes and go from there."

Roster move at fullback

The Bills made a roster move at the fullback position due to injury. Undrafted rookie Zach Olstad was waived/injured with an ankle injury. The club signed Sam Rogers to replace him and he's practicing today.

A former sixth-round pick of the Rams in 2017, Rogers was with Los Angeles until his release this past May after spending the 2017 season on their practice squad.