LB Keith Brooking made his official Broncos practice debut on Saturday. He worked with the second team at weakside linebacker.

Brooking signed with the Broncos last Monday after an offseason and early training camp without a team. His work on the field showed he has some rust to work off.

"It felt good. It didn't feel great, but it felt good," he said. "I felt like I had some decent pop in my legs, and my body feels great overall.  It's just the mental aspect of learning the defense."

Brooking even got into a brief tussle with C J.D. Walton -- one of multiple scrums that developed on a day where tempers ran a bit hot at times.  However, Brooking was not the intended target.

"(Walton) said, 'Man, I would not have picked a fight with you; I thought it was someone else,'" Brooking said. "Yeah, you should have seen me way back in the day.  It was like four or five in a day. So I've calmed down a lot. I'm much smarter."

Brooking will also receive a look at middle linebacker, where he made a brief cameo in during a non-contact seven-on-seven period last Tuesday. He also lined up as one of two linebackers in the second-team nickel package during Saturday's work.

PORTER INJURED: CB Tracy Porter strained an abdominal muscle midway through practice.  Porter was in coverage during a team red-zone drill and crumpled to the ground, but eventually walked back to the sideline under his own power to receive treatment. Porter's injury was not serious enough for him to go back to the locker room immediately; he watched the rest of practice from the sideline. Drayton Florence took his place at right cornerback.

SITTING OUT: LB Danny Trevathan and FB Chris Gronkowski joined the Broncos' list of wounded players, missing Saturday's work with ankle and groin injuries, respectively. Both were hurt during the preseason opener Thursday. OT Ryan Harris (ankle), DT Justin Bannan (calf muscle), WR Tyler Grisham (knee), S Quinton Carter (knee surgery) and S Jim Leonhard (knee, PUP list) remained sidelined.

WILLIAMS MISSING: For the first time this training camp, LB D.J. Williams was not at practice. Fox said he had an excused absence.  Williams had been at every session up until Saturday, but had yet to see a snap in team or seven-on-seven work.

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