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If DeMarco Murray is unable to play Sunday, the Philadelphia Eagles are comfortable that backup running back Ryan Mathews can carry a heavy workload against the New York Jets.

Like Murray, Mathews was a free-agent acquisition in the offseason, leaving the San Diego Chargers to sign a three-year deal with the Eagles. The move was somewhat surprising, coming on the heels of Philadelphia inking reigning league rushing champion Murray to a five-year, $42 million pact.

"You always have to have depth at running back and that was always the plan for us," Philadelphia coach Chip Kelly said. "We have tremendous confidence in Ryan and also in Darren Sproles, if DeMarco can't go."

Murray tweaked a hamstring in practice Wednesday and sat out Thursday, so his availability for Sunday's game will not be determined until Friday or Saturday. He's off to a dreadful start in Philadelphia, rushing for only 11 yards on 21 carries in the first two games.

Mathews, who has only four carries for four yards, was a first-round draft pick of the Chargers in 2010 and has had his moments - when he's able to stay on the field. The former Fresno State product owns a pair of 1,000-yard seasons, including a career-best 1,255 in 2013 - the only year in which he's played all 16 games.

Kelly said the Eagles will not change their game plan if Murray is unable to go Sunday and cited the similarities between his two running backs as a major reason why.

"You can do similar -- type things with them," Kelly said. "If you had a different type of back backing up or being the No. 2 guy, then it's a different deal, but that's one of the reasons we really had Ryan in here."

(h/t PennLive.com)