Broncos sign center Dan Koppen
Koppen, who turns 33 on Wednesday, adds experience and depth to the interior line and might push starting center J.D. Walton for playing time.
Manning was sacked twice in his Denver debut, once when it appeared the wrong line call shifted everyone to the right and led to left tackle Ryan Clady having no one to block. Running back Knowshon Moreno was left to block two men, and Pittsburgh linebacker Jason Worilds dropped Manning for an 8-yard loss.
The offensive linemen weren't in the locker room during the media access period Tuesday.
The Broncos also waived backup center C.J. Davis and re-signed backup quarterback Caleb Hanie, who was released in a procedural move Saturday to provide the Broncos with some financial flexibility. His $1 million base salary is no longer guaranteed.
As expected, the Broncos also placed defensive tackle Ty Warren on injured reserve after he re-tore his right triceps in the opener, his first game since 2009.
"It affects us a lot, actually," said second-year defensive tackle Mitch Unrein, who played a career-high 40 snaps after Warren got hurt. "He's a great leader. but as coach (John) Fox always says, next guy up, so that kind of opens the door for guys like me."
Warren, 31, re-injured himself early in the Broncos' 31-19 win over the Steelers. He missed all last season after tearing the same muscle during training camp, and he missed the 2010 season, his last in New England, with a hip injury.
Warren's return lasted two plays into the second quarter when he came up injured after shaking off a blocker and trying to tackle running back Jonathan Dwyer.
"That's a pretty sad reminder of how brutal this game can be and how quickly it can all be over," Unrein said. "This injury thing is tough, especially for how great he's played in the NFL for so many years and to go out that way, that's kind of a bummer."
Warren was the 13th overall pick by the Patriots in 2003 and he helped New England win two Super Bowls before signing a two-year deal in Denver in 2011. Although he restructured his contract over the summer, Warren will end up collecting more than $5 million for his five snaps with the Broncos.
Copyright 2012 by The Associated Press
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