Changing positions is not always easy, especially when it's an offensive tackle moving to guard. The techniques are different and learning to play in a more confined space makes the transition challenging.

There have been some rough spots along the way, but Buffalo Bills rookie Andy Levitre seems to be getting the hang of it.

The starting left guard more than held his own against the New England Patriots' tough interior defensive line on Monday night.

"I feel like it went really well," Levitre said after practice Thursday. "Collectively, the offensive line had a good night. Personally, my mind-set was just going out, executing my assignments and keeping mistakes down to a minimum. Watching it on film, there's always going to be some mistakes. But we'll work on correcting those and move on to the next game."

Levitre is one of two rookies on the Bills' offensive line. Eric Wood was a star center in college, but the Bills drafted him in the first round because they believed he could be a top-notch right guard.

Levitre played some guard at Oregon State, but started 19 games at right tackle and 17 on the left side over his last two seasons. His adjustment figured to take more time and it did.

But if his performance on Monday is an indication, the Bills' long and often frustrating search for a legitimate left guard since perennial Pro Bowler Ruben Brown departed in 2003 might finally be over.

"Andy's adapting well," offensive line coach Sean Kugler said. "With him and Eric switching positions, I thought Eric's transition would be quicker moving from interior to interior. Going from tackle to guard is a bigger transition, and probably at the beginning Andy did

start a little bit slower. But he's really been catching on. I think he's really bought into that position. He's working hard and getting better each day he's out here."

Levitre couldn't ask for a better first test in Vince Wilfork, the Patriots' mammoth defensive tackle. Levitre didn't win every battle with Wilfork, but he won his share against a guy who usually swallows up far more experienced offensive linemen.

"He's a lot bigger in person than on TV," Levitre said with a wide grin. "It was a challenge, but I feel that we did a pretty good job against him."

Just as impressive was the mobility Levitre showed getting downfield and getting hits on linebackers. He also excelled on screen passes, getting blocks that helped spring running back Fred Jackson on some big plays.

Jackson finished with a team-high 57 yards rushing on 15 carries and 83 yards on five catches against the Patriots' defense.

"That was the thought, getting guys in there at that position who were going to battle and compete," Kugler said. "We need guys in there who can match up with guys like [Wilfork] and be athletic enough to get out in space. Andy did a nice job and we expect him to take another

step forward each week."

Some habits are hard to break, though. Tackles are in an upright stance most of the time, while guards have to keep their pad level low and they can play with better leverage.

Levitre still has a tendency to come out of his stance too high at times. That makes it harder to anchor and hold his ground against bull-rushing defensive linemen.

But that part of Levitre's game, according to Kugler, is coming along.

"That will be a constant battle with Andy, and that's something we work on every day," Kugler said. "The problems he's gotten into in the preseason and the first game is with pad level. But he works at it. When his pads are down Andy can be very effective."

Levitre feels the time he had in the offseason workouts to play guard shortened his learning curve significantly. Now it's a matter of building on his promising start.

"I just want to keep improving and get to where I can be consistent on every play and every game," he said. "I'm not there yet, but I think I'm moving in that direction."