Dallas Cowboys head coach Brian Schottenheimer has challenged his team’s backup running backs to step up this season. Dallas leaned heavily on Javonte Williams, who had a career resurgence with 1,201 yards. He also had a total of 287 touches, plus a number of massive blocks in pass protection, which was the likely cause for his nagging late-season shoulder injury . The next most touches for a running back came courtesy of Malik Davis, who had just 52 rushing attempts and two receptions. That’s why Schottenheimer is asking for more, with second-year back Jaydon Blue offering the most potential . Blue was also someone we named as a big winner after the NFL draft , since the Cowboys didn’t select anyone to challenge him for snaps. That said, Bleacher Report’s Kristopher Knox sees a scenario where the Cowboys make a move for a more proven option, naming them a potential landing spot for Alvin Kamara . Will Alvin Kamara be traded this year?…