's has hit a snag.Johnson was diagnosed with a fractured tibia after leaving in the third quarter, NFL Media Insider Ian Rapoport reported, per a source informed of the injury, on NFL Network's Dixon Machado Jersey Monday edition of .Fox Sports' Jay Glazer first reported the news.The placed the 30-year-old tailback on the injured reserve/designated for return list on Tuesday. Johnson will be eligible to return for the if the advance through the Niko Goodrum Jersey NFC playoffs.The injury will prevent Johnson from chasing a $2 million incentive that would have triggered with a 1,300-yard season and a trip to the . He had been on pace for 1,184 rushing yards and 1,268 yards from scrimmage prior to the injury.Arizona is one of the few teams with the quality depth to withstand such an injury to its leading rusher. The i sue is compounded, however, by a turf toe ailment that sent to the sidelines minutes Victor Martinez Jersey after Johnson left.The will turn to , who became the first player in NFL history to score a touchdown via run, pa s and kick return in his first two games -- back in September Ryan Carpenter Jersey .Appearing on SiriusXM NFL Radio Tuesday, coach Bruce Arians confirmed that the rookie will be "" and is "" for the role.The former Northern Iowa star will be backed up by and until Ellington kicks the turf toe injury.Although the elder Johnson was the talk of the league while averaging 5.9 yards per carry in October, he managed a paltry 3.0 yards per rush in November. One of the NFC West leader's few Josh Harrison Jersey concerns has been Johnson's lack of punch in short-yardage situations.It's quite po sible that the younger Johnson will prove to be an upgrade in a withering ground attack.