Tony Sparano is unprepared to declare impressive Raiders running back Latavius Murray as his featured guy. And that has some fans upset.

Murray rushed for 155 yards in his last eight carries before missing the Week 13 game with a concussion. That's as many yards as starter Darren McFadden has in his last 62 attempts, but Sparano remains skeptical.

"He has eight carries," Sparano pointed out to the San Francisco Chronicle. "I love the way Latavius runs the football. I like what I've seen. I've seen eight carries. I want to see more of him. I'm curious, too. I'm curious just like the fans are curious."

Sparano has stated that he would like to see Murray get 15-18 carries in a game to see how he responds. Oakland hosts San Francisco on Sunday, but Murray will certainly not be used exclusively in the backfield.

"For now, he's going to be a guy you continue to rotate," Sparano said.