Tell III's grade of 88.8 against Buffalo is the fourth-highest grade among all NFL cornerbacks currently this preseason, and the highest among all rookie corners. Although Tell III was given of grade of 62.6 in the run game, his coverage grade was a 90.2.

As mentioned, he was targeted twice but allowed no completions and had one pass breakup. He was also credited with three special teams snaps on the kickoff coverage unit.

Colts defensive coordinator Matt Eberflus has been impressed with Tell III's ability to learn a new position on the fly so far through training camp.

"He's doing well, he's doing well," Eberflus said on Sunday. "When you switch from safety to corner there are a lot of nuances, a lot of techniques and fundamentals that he has to learn. We are working with him day-to-day on that.

"Then we have to learn what his body can do. What can he do personally? Then who is he covering? And then what can he do? So you have to look at all the variables there. He's starting to learn that and that's an experience. He has to go through the experiences of that," Eberflus continued. "That's why having Cleveland in here and having him cover different wideouts on our squad is so important — and him really knowing himself as well as he knows the opponent he's going against."

Tell III's supreme athleticism allows him to hang with receivers downfield, and he can close in on them in a hurry on short to intermediate routes. Tell III's length (6-foot-2 with an 80-inch wingspan) allows him to break up passes that many other cornerbacks wouldn't be able to reach.

He is also getting comfortable enough at this point to take more chances when defending the ball, firing in to break up pass attempts.

Since last Thursday's game, in Sunday's practice, Tell III broke up a pass along the left sideline that resulted in fellow defensive back Rolan Milligan intercepting the pass off the deflection. On Monday, quarterbacks were wary about throwing downfield in Tell III's direction because of his tight coverage. He still managed to break up a pass attempt thrown in his direction early in practice.