OXNARD, Calif. -- The battle for the starting left guard spot for the Dallas Cowboys might be heating up in part because of an injury.

According to a source, the starter, Ronald Leary, will get an MRI on his sore back, which has kept him out of two practices in training camp.

With Leary resting, rookie La'el Collins will get the first-team snaps at left guard. The only time Collins has taken snaps with the No. 1 offense has come when Leary has not practiced, which is a sign there has not been a true fight for the position.

Collins played well in his preseason debut last week against the San Diego Chargers after taking over for Leary in the second series of the game.

The Cowboys don’t believe Leary’s injury is major, but it will be something they will have to manage for a little bit.