James Conner injured his ankle during the second half of Sunday's loss to the Chargers. (AP Photo/Gene J. Puskar)

The Pittsburgh Steelers went into the season using Plan B at running back thanks to Le’Veon Bell’s holdout, and for 12 games it’s worked out far better than anyone could have imagined. Second-year running back James Conner has been a revelation, with 909 yards and 12 touchdowns on the ground along with 52 catches for 467 yards.

For at least one week, however, Plan B will not be an option. Conner injured his ankle in the second half of Sunday night’s loss to the Chargers and will miss the Steelers' road game against the Raiders in Week 14, Coach Mike Tomlin announced Tuesday.

Conner originally was thought to have suffered a lower-leg contusion, but tests revealed that the injury was more serious and Tomlin said Conner had suffered an ankle sprain.

Tomlin told reporters that the Steelers' Plan C against the Raiders will involve some combination of Jaylen Samuels, who has 12 carries for 31 yards as a rookie this season, and veteran Stevan Ridley, who has 18 carries for 56 yards. Samuels is more likely to catch passes out of the backfield: Two of his seven receptions this season have gone for touchdowns. Ridley has just 30 catches in 71 career NFL games. The Steelers also signed Trey Edmunds (nine career NFL carries) off their practice squad.

Conner topped 100 rushing yards in five of Pittsburgh’s first eight games but hasn’t rushed for more than 65 in any of its last four, though he did score twice against the Chargers. The Raiders offer a chance for the Steelers to get right on the ground, however: Oakland is giving up 153.2 rushing yards per game, which ranks 31st out of 32 NFL teams.

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