Orchard Park, NY ? Running back Willis McGahee is out indefinitely with three broken ribs, leaving the Bills without their best offensive threat against the Indianapolis Colts this weekend.

Coach Dick Jauron on Wednesday ruled McGahee out, adding the player’s injury is more severe than initially thought. Jauron said follow-up tests showed McGahee damaged three ribs in Buffalo’s 24-10 win over Green Bay last weekend.

McGahee was originally diagnosed with one broken rib and later tests showed breaks in two others.

Jauron did not say how much time McGahee might miss, and said his return will depend on the healing process and the player’s tolerance to play with pain.

Tampa Bay tight end Dave Moore missed four weeks after breaking a rib earlier this season.

When McGahee does return, he’ll likely have to wear a protective jacket.

Jauron also announced Josh Reed is out indefinitely. The backup receiver spent two days in a Buffalo-area hospital this week after bruising his kidney against Green Bay.

“It depends on how you define a while, but definitely not this week, and it could easily go longer,” Jauron said of Reed. “We’ll be conservative.”

Buffalo running back willis mcgahee is helped by trainers after breaking his ribs. He is out indefinitely after Sunday's injury in Orchard Park, N.Y.

Without McGahee, the Bills will turn to Anthony Thomas, the 2001 NFL rookie of the year who joined Buffalo as a free agent last spring. Thomas had 20 carries for 95 yards and a touchdown filling in for McGahee on Sunday.

A second-round pick out of Michigan, Thomas spent four seasons with Chicago before splitting last year between Dallas and New Orleans, combining for a career-low 92 yards rushing and no scores.

Thomas already has two touchdowns with the Bills this season, and ranks second on the team with 134 yards rushing.

“I never had any doubts that I could do it,” Thomas said of his resurgence this season. “I believed in myself and I knew when the opportunity would come, I could go out there and do it.”