"Aaron Williams' "welcome to the NFL moment" came in the first preseason game of the summer in Chicago.

"I was going against a screen to the tight end," Williams recalled. "It was me and him mano-a-mano. He was 6-6, 265 pounds. You're a rookie, and you know the vets are looking, so you can't miss that tackle. I tried with all my heart to go with my full body. I hit him and I got him down. But I was shaken up. I couldn't get up for awhile."

Williams showed a physical style early and often enough throughout his rookie season to make him a favorite for a starting position next season. Size and athleticism are the reasons the Bills took him with their second pick in the 2011 NFL draft. At 6-foot-0 and 200 pounds, Williams is the biggest cornerback on the Bills' roster, and he's not afraid to throw his body around.

Injuries prevented Williams from making a major impact on the Bills, the kind first-round pick Marcell Dareus made. Williams missed six games early in the year due to a collarbone injury then missed a December game with a strained calf. However, in nine games he managed to play about 42 percent of the total defensive snaps for the year. He made 32 tackles, had one interception and defensed five passes.

"Aaron played fairly consistently for a rookie ... when he finally got his chance," coach Chan Gailey said. "He battled injuries all year long, and that's always tough on a guy. That's the one thing that we've got to hopefully do is train him in the offseason and get him where he can make a whole season without the injuries. I thought he showed potential to be a very good corner in this league for a long time. He matches up well size-wise.""