LAKE FOREST, Ill. — The Chicago Bears placed Nathan Vasher on injured reserve today with a broken right hand, ending the defensive back's season.

Vasher, who'd been sidelined for three games earlier this season with a right wrist injury that required surgery, fractured his hand in Sunday's game against the St. Louis Rams. He also re-injured his thumb.

Vasher, who was chosen for the Pro Bowl in 2005 when he had eight interceptions, appeared in eight games this season, including seven starts. He recorded 29 tackles with one interception and three pass breakups.

Vasher, who appeared in only four games last season because of a groin injury, has 18 career interceptions, but only two in the past two seasons.

Corey Graham is expected to move into his starting role for Sunday night's game against the Minnesota Vikings.

The Bears also activated fullback Jason Davis from the practice squad. Starting fullback Jason McKie pulled a quad muscle in practice Friday and his availability for Sunday was not known.

Davis, who entered the NFL as an undrafted free agent with the Eagles in 2006, spent last season on Philadelphia's practice squad. After being cut by the Eagles at the end of this year's preseason, Davis signed with the Bears practice squad on Sept. 1. He was signed to Oakland's active roster on Oct. 28 before being waived by the Raiders last week. He appeared in one game with the Raiders while being inactive for two others.