The nerves nearly got the best of Trent Williams last Friday night.

The fresh-faced rookie said he was "gassed" after three plays."

Williams settled down and played the entire first half of the Redskins' 42-17 preseason victory over the Buffalo Bills.

From all accounts, Williams impressed in his NFL preseason debut. He did not yield a sack and was an active blocker in the ground game.

"It felt good to be out there," Williams said. "It was something to build off of."

Williams' development in the offense is key this preseason. As the Redskins' first-round draft pick (fourth overall) last April, he is expected to start at left tackle in Week 1 of the regular season.

On Sunday afternoon at Redskins Park, Williams was back on the practice field with a host of things to work on.

Technique. Footwork. Formation. Snap count.

The game film revealed plenty of mistakes.

"I can get a lot better, I feel like I did okay," he said. "When I'm looking at [the game film], I'm looking at a lot more than guys trying to get by me [on a pass rush]."

Midway through the second quarter, Williams was whistled for an illegal formation penalty, negating a short pass from Rex Grossman to Keiland Williams that turned into 28-yard gain.

Head coach Mike Shanahan said that Williams lined up too far in the backfield on the play.

"I thought he did a good job overall," Shanahan said. "He had one penalty in there, that one dump that he had called back. We had him lining up too far in the backfield. But overall I am very pleased for his first game."

Center Casey Rabach was also keeping an eye on Williams during the game.

The offensive game plan was vanilla enough to allow coaches to evaluate players on some basic plays, Rabach said.

"I think [Williams] held his own, he really did," Rabach said. "I think there's room for improvement, too."