Daniel Thomas has said that he is trying to be the "complete" running back at the Miami Dolphins' training camp.
The 25-year-old is beginning his third season with the Dolphins, but has started just two games since entering the league in 2011.
He told the team's official website: "Just doing the little things. I think I have to separate myself in the pass protection. I got to be able to be on the field all three downs and protect the quarterback. If you can't do that, then you won't be able to play.
"As the pre-season goes along, coach said we are going to get more series in, so hopefully we'll get more plays in. I just want to continue to get better in practice and take it to the game."
Offensive coordinator Mike Sherman added: "I think from a running standpoint we have some pretty good runners, but to be the complete back, they have to be able to do all of those things. That'll be the true test on who ends up being the starter, I believe."
Thomas has had eight carries for 24 yards during the Dolphins' pre-season games against the Dallas Cowboys and Jacksonville Jaguars.