Cardinals put RB Chris Johnson on IR

The Arizona Cardinals placed running back Chris Johnson on injured reserve/designated for return on Tuesday with a fractured tibia.

Johnson, who was injured during the third quarter of Sunday's 19-13 win over the San Francisco 49ers, will be eligible to return after six weeks and able to play in a game after eight weeks. That would leave Johnson available only if the Cardinals reach the Super Bowl.

The Cardinals (9-2) also lost running back Andre Ellington with turf toe after Johnson's injury on Sunday.

The loss of the two backs will force Arizona to turn to David Johnson, a 2015 third-round draft pick, as the starter. The rookie made a splash earlier this season, becoming the first NFL player to score on a run, pass and kick return in his first two games.

Backing up David Johnson at running back will be Stepfan Taylor and Kerwynn Williams, who was promoted from the practice squad.

Chris Johnson was having a big comeback season before the injury. He ranks fourth in the NFL in rushing with 812 yards, putting him on track for his first 1,000-yard season since 2013.