Hearst, Bell move up the depth chart

Second-year running back Quentin Griffin, who began the season in the Denver Broncos' starting lineup, will finish it on injured reserve.

An MRI of Griffin's right knee Tuesday confirmed that he suffered a torn anterior cruciate ligament in Monday night's loss to the Bengals. The Broncos had feared as much and even indicated after the game that initial indications were that the injury was serious.

The loss of Griffin further thins a once-robust backfield and likely means former fullback Reuben Droughns, who has started the last three games and rushed for more than 100 yards in each, will remain in the lineup. Denver earlier lost Mike Anderson for the season to a severe groin injury.

With Griffin lost, rookie Tatum Bell and veteran Garrison Hearst will move up the depth chart. Signed as an unrestricted free agent in the offseason, Hearst did not dress in five of the first seven games. Ironically, ESPN.com learned that Hearst met with coach Mike Shanahan two weeks ago about his role and was told that there would come a point in the season when he would be needed. That turned out to be, it seems, a self-fulfilling prophecy.

Griffin, 23, won the starting job in camp, earning the right to replace the departed Clinton Portis, who was traded to Washington for cornerback Champ Bailey, despite having run for more than 1,500 yards in each of his two seasons with the Broncos. Griffin rushed for 156 yards and three touchdowns in the opener, but also fumbled three times in the first three games, and came under close scrutiny.

He started the opening four games, then sustained an ankle sprain, which sidelined him for one game. Griffin will undergo surgery within the next week or two, once swelling subsides in the knee, and he probably faces a rehabilitation period of six-to-nine months.

On Wednesday, Denver officially placed Griffin on injured reserve, elevated running back Cecil Sapp off the practice squad and signed Kris Briggs to the practice squad.

"I'll be all right," Griffin said as he left the team's
training facility on crutches. "I've just got to do a lot of

Last week, Griffin was used on kickoff returns and that was his role again Monday night. He lasted only three return plays before the ankle injury.

Len Pasquarelli is a senior NFL writer for ESPN.com. To check out Len's chat archive, click hereInsider.

Information from The Associated Press was used in this report.