ENGLEWOOD, Colo. -- Rookie cornerback Bradley Roby put pen to paper Tuesday and signed his four-year deal with the Denver Broncos.

The no-stress signing of a first-rounder that has come with the league’s rookie wage scale was typically without drama for Roby and the Broncos. But it does put a bow on the Broncos’ six-player draft class, now all signed and sealed. The signing also continues Roby's official progression toward some serious playing time in the season to come.

If the team's offseason workouts are any indication, including Tuesday's practice, the first of a three-day mandatory minicamp for the team, the Broncos have stuck to the plan with the Roby. They said they selected Roby with the 31st overall pick of the May draft with the idea he could contribute immediately, and so far, Roby has held up his end of the bargain.

"I've been very impressed," said Broncos head coach John Fox. "It’s not too big for him. He’s obviously got the physical skills. ...I've been really impressed with what he’s done, how he’s conducted himself as a Bronco thus far."

Roby signed his four-year deal Tuesday for $6.95 million overall with the $3.376 million signing bonus. And with cornerback Chris Harris Jr. still working his way back from ACL surgery, Roby has been pressed into action with the defensive regulars more than he may have been if Harris Jr. was completely healthy.

But for a team that played nickel (five defensive backs) almost 70 percent of the time, Roby's progress is on the front-burner. The Broncos see him as a physical cover corner who can both jam receivers at the line of scrimmage and run with them in the open field -- John Elway has called him a "top 15 talent" on this year's draft board.

Roby and Aqib Talib project as the two outside corners in the nickel with Harris Jr. dropping down into the slot. At least for the moment, with Harris Jr. expected to be full speed for the opener, Harris Jr. and Talib would start in the base defense.

But Roby has been a quick study so far, aggressive in practices, including knocking a ball away in the two-minute drill Monday when quarterback Peyton Manning tried to push the ball into traffic. The Broncos did have a scary moment in that same two-minute drill when Roby and wide receiver Emmanuel Sanders collided on a crossing route.

Roby briefly left the field and removed his helmet, but returned on the next play.

"There are collisions, it’s a combative game," Fox said. "You try to avoid it as best you can, but sometimes you’re not going to be able to avoid all the situations, but they both popped up and everything’s good."