"I know they're coming," Claiborne said, via ESPN.com. "During game times I know they're coming. I knew they were coming then."
Claiborne had wrist surgery prior to April's draft, and was held out of all previous offseason workouts. He's been fitted with a brace, which he will wear for the duration of his rookie season.
"It's hard to estimate how behind he is," Cowboys coach Jason Garrett said. "He is (a) rookie trying to play in the NFL. This is his first practice. We had 12 practices in the spring and he missed all of those. He was very engaged in the team. We will practice tomorrow, practice on Friday, then go to camp and start up again on Monday so he will get a lot of work on a short period of time."
Claiborne has to play catch-up, but he should still be in good position to win the right cornerback job out of camp. The Cowboys didn't trade up to the top of the first round if they didn't believe Claiborne could be an instant factor.