Posted by ESPN.com's Bill Williamson
Broncos center Tom Nalen is out for Sunday's home game against New Orleans.
Nalen, 37, had been practicing on a limited basis and is coming off his second knee surgery of the summer in August. It may be several weeks before Nalen, who missed the final 11 games of last season with arm injury, can return.
Casey Wiegmann steps in at center and has done a good job recently in spot duty. Denver quarterback Jay Cutler has been sacked just once but that was the controversial fumble against San Diego on Sunday.