Fred Jackson, C.J. Spiller injured

ORCHARD PARK, N.Y. -- The Buffalo Bills lost running backs Fred Jackson and C.J. Spiller during Sunday's game against the Minnesota Vikings as both were carted off in the first half of the Bills' 17-16 win and didn't return.

Jackson suffered a groin injury, while a source told ESPN NFL Insider Adam Schefter that Spiller broke his collarbone.

Bills coach Doug Marrone said after the game that Spiller will be out "for an undetermined time."

Jackson stayed down on the field after a third-and-1 run in which he was stopped short of a first down. Jackson was eventually helped to his feet and walked to the sideline with assistance from center Eric Wood and a trainer.

A cart later took Jackson, with hands covering his face, to the locker room.

Spiller took his first carry of the game 53 yards to the Vikings' 15-yard line but came down hard on his shoulder. He remained of the ground for several minutes before being carted off.

Jackson, 33, is the NFL's oldest running back and the Bills' most-tenured offensive player. Through the first six games this season, Jackson ran 52 times for 227 yards and one touchdown. He added 30 catches for 245 yards and a touchdown.

The Bills were down to one healthy running back -- Anthony Dixon -- for Sunday's game. Bryce Brown, acquired this offseason, is inactive.