Darren McFadden has halted contract talks with the Oakland Raiders, according to NFL.com.
The running back is heading into the final season of his rookie deal with the AFC West side, having been a first-round draft pick in 2008.
The team's head coach Dennis Allen told the league's website: "Obviously, he never felt comfortable in what we were doing last year.
"That led to some questions about him, but if you watch practice, the guy's still explosive. He's still a threat to take it all the way. And he feels more comfortable. If you don't quite trust it, there's always that doubt."
The 25-year-old has missed 13 games in the last two seasons with injury.
