Competition at various positions has been the talk of camp so far, from kicker to running back and defensive back.
One position where coaches did not expect competition was fullback, where Darrel Young is entrenched in his second season as a starter.
But when Shanahan announced yesterday that Young would be out one-to-two weeks with a minor hamstring injury, a new competition was born.
"Tailbacks got to play fullback, our tight ends got to play full back," Shanahan explained. "We will find out which is the best group."
Second year running back Evan Royster was getting some recent repetitions at fullback, but he suggested that he one of many trying out the position.
Rookie back Alfred Morris understands that versatility between positions can increases your chances of making the squad, and was given some opportunity during offseason workouts.
Right now, the player likely to get most of the snaps is recent free agent signee Dorson Boyce. Boyce was inked right before the start of training camp, after spending last year's training camp in Seattle.
Boyce is still learning the playbook, but with Young out of practice, he has more repetitions to learn on the fly.
"For me right now, it's just getting in that playbook and perfecting my craft," Boyce said. "You just want to compete, that's the overall goal so I'm out there every day. I'm doing the best I can to try to help this ball club."
Meanwhile, Young is simply hoping to get healthy and prepare for a healthy regular season.
Young previously injured the same hamstring last season. By his estimation the injury this time around is not as severe and he will rest it as a precautionary measure to get back to 100 percent.
"I'm on the treadmill walking a little, to make sure I can walk normal," Young said about his rehab. "The biggest thing is making sure I don't walk with a limp, so the muscle gets used to that and I pull it again."