Our Cowboys sources have suggested for months that the team's RB situation would be changing in 2011. Following the draft, which saw the selection of third-rounder DeMarco Murray, the picture is becoming more clear. Murray enters the mix along with Felix Jones and Tashard Choice, as it appears the team is moving on without Marion Barber. It's possible that Barber could be released once player movement is permitted again. His salary has become too cumbersome for a player whose supposed strengths — running inside, especially — appeared muted last season. Durability is also a concern. But that also is the case for Jones and Murray, who had an injury-plagued career at Oklahoma. When healthy, he appeared to be a future star, but he often was not able to compete because of nagging ailments. In order for the rookie to show he should be in the regular mix on offense, he must beat out Choice and prove to be more of an every-down back than Jones, whose skill set might limit him to screens, draws and the occasional stretch play.