SANTA CLARA, Calif. -- Kyle Williams circled this week's game against the New York Giants as soon as the NFL schedule was released in April.

He and his San Francisco 49ers teammates have some unfinished business against the Super Bowl champions.

Williams' two turnovers on punt returns played a key role in helping the Giants win last season's NFC Championship Game 20-17 in overtime, costing San Francisco a trip to the Super Bowl.

"There's a few teams that I look forward to. Of course after what happened last year I definitely want to get back at these guys," Williams said Tuesday. "We look at it as if they have something that we should have had. We're going to make sure we don't leave anything on the field again."

Williams and the Niners (4-1) get their chance against the Giants (3-2) on Sunday in a rematch that has far less at stake than that meeting last January.

Williams played a central role in that game as a fill-in punt returner for the injured Ted Ginn Jr. Early in the fourth quarter, Steve Weatherford hit a short, bouncing punt that Williams came up to try to field. He backed away at the last minute, but the ball glanced off his right knee and was recovered by Devin Thomas at the San Francisco 29. That set up New York's go-ahead score.

Williams helped atone for his miscue when he returned the ensuing kickoff 40 yards to help set up David Akers' tying field goal late in regulation.