Chris Simms ' comeback is nearly complete.

The backup quarterback for the Denver Broncos took the snaps with the starters again Thursday, making it increasingly likely he'll start against San Diego on Sunday in place of Kyle Orton , who hasn't practiced since spraining his left ankle last week at Washington.

Simms hasn't started a game since Sept. 24, 2006, when he played for the Tampa Bay Buccaneers and was battered so badly by the Carolina Panthers that he needed emergency surgery to remove his spleen.

After losing two-thirds of his blood and spending five nights in intensive care, Simms' comeback was a long and arduous one with more speed bumps and dead ends than he'd like to remember.

He missed the remainder of the 2006 season and all of 2007. After the Bucs granted him his release, he hooked up with the Tennessee Titans last year and threw just two passes while mopping up the regular season finale.

This spring, he signed a two-year, $6 million free agent deal to be the Broncos' backup.

Around the league

Vikings » The team signed coach Brad Childress to a contract extension. ESPN.com cited anonymous sources in reporting that the extension will carry through the 2013 season.

Redskins » Running back Clinton Portis will miss his second straight game as he recovers from a concussion. Coach Jim Zorn ruled Portis out for Sunday's game at Dallas.