Veteran linebacker Keith Brooking, who has played 14 seasons in the NFL with the Cowboys and Falcons, worked out for the Broncos on Monday morning. A few hours later, he was signed and watching practice, although his full-contact debut will have to wait a few days, since the Broncos have practices in shorts Tuesday and Wednesday.

Brooking, 36, said he expects to work at the middle and weakside linebacking positions, providing depth to a pair of slots where they don't have experienced reserves. The current second-teamers at middle and weakside linebacker, Mike Mohamed and Nate Irving, are 2011 draft picks who have combined for one career tackle on defense.

Unlike safety Jim Leonhard, who the Broncos signed Saturday, Brooking does not expect to be put on the active/physically unable to perform list and expects he will be practicing by Saturday.

"I haven't been in the offseason program, so I'd be lying to you if I said that I was in game shape and ready to go, but my legs feel good; they still have pop in them," Brooking said. "I had a lot of blows to the head and a few surgeries. I'm not what I was eight years ago, but relatively speaking, my body feels really good."

Banged up: WR Demaryius Thomas was held out of most of the team and seven-on-seven periods because of what Broncos coach John Fox termed a "tight Achilles."  Thomas tore an Achilles tendon in February 2011, but Fox said that Monday's issue was "nothing serious." ... OT Ryan Harris left practice with a right ankle injury ... RB Mario Fannin will be placed on injured reserve with a torn Achilles tendon once he passes through waivers.

Backup battle: After declaring reserve quarterbacks Caleb Hanie, Brock Osweiler and Adam Weber as "2a, 2 and 2c" last week, Fox and the Broncos released a depth chart listing Hanie as the second-teamer, followed by Osweiler and Weber. Fox implied that the listing was by no means final. "The people can make a lot out of this chart we hand out," Fox said. "Really, we only put it out there because we have to for the other teams."

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