ORCHARD PARK, N.Y. (AP) First, Fred Jackson was carted off. Then, C.J. Spiller.
And it's unclear when the Buffalo Bills one-two punch running back tandem will be healthy after the two were hurt 10 minutes apart in the first half of Buffalo's 17-16 win over Minnesota on Sunday.
Spiller, who was carted off in tears, hurt his left shoulder and will miss what coach Doug Marrone called ''an undetermined amount of time.''
As for Jackson, the Bills are waiting for further tests to determine the severity of the groin injury the veteran running back sustained late in the first quarter.
The injuries deplete Buffalo's offensive backfield, which was down to running back Anthony Dixon and fullback Frank Summers. The Bills have one other running back on their roster, Bryce Brown, who has been inactive so far this season after being acquired in a trade with Philadelphia in May.
Buffalo (4-3) plays at the New York Jets this weekend before entering its bye week.
Marrone expressed confidence in his team's depth at running back.
''It's not like we have to go out on the street to get somebody to come in,'' Marrone said. ''I have no problem bringing up Bryce. We talked about (playing him) last week, which I hoped wasn't a jinx.''
Dixon had 51 yards rushing, and three catches for 15 yards in a game the Bills won on Kyle Orton's 2-yard pass to Sammy Watkins with 1 second left.
Jackson was hurt while rushing up the middle for no gain on a third-and-1. He immediately grabbed the inside of his left leg as he was on the field.
Jackson required help getting up and had difficulty moving his legs while being helped to the sideline by center Eric Wood and a trainer. He then had his head in his hands while being carted off.
Spiller was hurt as he fell hard to the turf after being tripped up from behind by safety Robert Blanton.
Spiller was in immediate pain as he rolled over on the left sideline. A towel was placed over Spiller's head as he was carefully loaded onto the cart.
Bills starting safety Aaron Williams did not return after aggravating a neck injury in the second half.
The Vikings (2-5) lost offensive line starters to injury. Center John Sullivan did not return after sustaining a concussion. Right guard Vladimir Ducasse did not return after hurting his right knee.
Coach Mike Zimmer said he had ''no idea'' when asked if either has a chance to play at Tampa Bay next weekend.
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