ALAMEDA, Calif. (AP) -- The Oakland Raiders may have to reach way down on the depth chart to fill out their backfield for Sunday's game in New York.
Darren McFadden is sidelined again, this time with an ankle injury. Rashad Jennings has made progress since sustaining a concussion last week but has yet to be cleared. Not even third-stringer Jeremy Stewart, who is nursing a combination of ankle and knee injuries, was able to practice Wednesday.
That forced the Raiders to turn to a player who hadn't taken a single snap at running back since 2012.
Taiwan Jones, a fourth-round pick who was converted to cornerback during the offseason, practiced with the first-team offense and could conceivably start against the Jets if Oakland's injured running backs aren't able to do so.
''Once I got out there everything started coming naturally, just like riding a bike,'' said Jones, who is also one of Oakland's top special teams players. ''The more reps I got, the more comfortable I was. We've got a lot of backs down ... so just in case. You've got to prepare for the worst.''
The oft-injured McFadden has already missed four games this season with hamstring injuries. He came back to play against Dallas on Thanksgiving, but carried just five times for 13 yards and apparently injured his ankle at some point during the 31-24 loss.
The fourth overall pick in 2008, McFadden was unable to practice Wednesday and his status for Sunday is uncertain.
''It's more than what we initially had thought so he wasn't able to go today,'' Raiders coach Dennis Allen said. ''Hopefully we'll be able to get him out there soon but I don't know.''
Jennings' situation is just as questionable.
The veteran backup leads Oakland with a career-best 588 yards and has provided Oakland's running game with a much-needed boost while McFadden has been out. Jennings, however, has not been cleared to play since getting hit late in the fourth quarter against Dallas after catching a short pass from quarterback Matt McGloin.
Jennings, who missed the final four games of the 2012 season with Jacksonville because of a concussion, passed some of the tests required by the NFL for players with concussions and was limited in practice.
With Stewart joining McFadden on the list of players not practicing, Jones was pulled off defense and inserted into the offense.
Later in the Raiders' locker room, Jones got confused when the players began leaving for meetings. He wasn't sure whether to go to the offense or defense.
''I'll just start with special teams and go from there,'' Jones said.
Allen didn't seem too concerned, even though the Jets own the NFL's top-rated run defense.
''We have to be prepared with the guys that we have to have somebody step up,'' Allen said. ''Taiwan's done a great job for us all year long on special teams. He's played at a Pro Bowl level, so having a guy with that type of versatility that can go over and play defense but yet can be a guy that can get us some snaps on offense if need be will be big for this game.''
The Raiders' ability to run the ball could directly affect McGloin.
Oakland's undrafted rookie starter passed for three touchdowns without an interception when the Raiders piled up 165 yards on the ground against Houston on Nov. 17. They've had just 143 rushing yards over the past two games, however, and McGloin's performance has dipped accordingly.
While he's passed for 515 yards in the two games - both losses - McGloin has thrown just one touchdown with two interceptions.
''I know the backs are helping each other out right now with different things,'' McGloin said. ''I have no doubt whatever guy that's in there will get the job done.''
NOTES: Strong safety Tyvon Branch practiced for the first time since injuring an ankle against Jacksonville in Week 2. ... Former starting left guard Lucas Nix worked at right guard with the starting offense, while Mike Brisiel sat out practice with a knee injury. ... WR Denarius Moore (shoulder), S Usama Young (neck) and LB Kaluka Maiava (calf) did not practice.
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