TEMPE, Ariz. (AP) -- Arizona coach Bruce Arians says the availability of running back Andre Ellington on Sunday at Philadelphia will be ''a game-time decision.''
Ellington injured his left knee late in practice on Thursday and sat out Friday's workout.
The loss of the dynamic rookie from Clemson would be a significant blow to the Arizona offense, because he provides speed the team's other backs don't possess.
Although he didn't carry the ball at all in the season opener, Ellington leads the Cardinals in rushing with 441 yards on only 73 carries, an average of 6 yards per carry. He also has 28 receptions for 247 yards.
Ellington said an MRI ''showed some stuff,'' but he wouldn't say what.
''We'll see how it goes,'' he said on Friday. ''We've got two days before the game. That's a lot of rest, two days. I'm going to continue to rehab and go out there on Sunday and run around a little bit.''
If Ellington can't play, the Cardinals still would have starter Rashard Mendenhall, rookie Stepfan Taylor, and Alfonso Smith at running back. The other back on the roster, Ryan Williams, has been inactive for every game this season, including one Mendenhall missed due to a toe injury.
With Mendenhall out for that game Oct. 27 against Atlanta, Ellington rushed for 154 yards in 15 carries, including an 80-yard touchdown run, in Arizona's 27-13 victory. The Cardinals (7-4) have not lost since, taking a four-game winning streak into their game against the Eagles (6-5).
The sixth-round draft pick has been a pleasant surprise, working his way into the offense with impressive play in practice and in the preseason.
Arians said Ellington's absence would force a minor adjustment in the game plan.
''The only thing is there are certain parts of the offense no one else will do, five or six plays that you would just take out,'' Arians said. ''Other than that just keep on rollin'.''
Arians downplayed the significance of the injury.
''Tweaked his knee a little bit yesterday,'' the coach said. ''Nothing real serious about it, but we want to be very careful with him.''
Ellington said he was hurt during a passing drill.
''I just turned the wrong way when I ran my route,'' he said, ''but other than that everything's fine.''
Arrington rushed for 50 yards on 10 carries and caught two passes for 21 yards in Arizona's 40-11 rout of Indianapolis last Sunday. Mendenhall, who had been bothered earlier with the sore toe, had his best game of the season in that win over the Colts, rushing for 54 yards in 13 attempts.
''There's still a bunch of guys that are capable of taking his place,'' Arians said, ''and we'll make our adjustments that we need to make.''
Mendenhall had his best game of the season in the win over the Colts, rushing for 54 yards in 13 attempts.
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