SAN FRANCISCO – Kyle Williams' name now belongs to a list that includes Preston Riley, Trey Junkin, Billy Cundiff and every other NFL player whose fumble, botched snap or missed kick has cost his team a playoff victory.

Williams, substituting for the injured Ted Ginn on Sunday, muffed one punt return in the fourth quarter that led to a Giants touchdown and then, on a play that will go down in 49ers playoff lore, fumbled away another in overtime deep in 49ers territory. The Giants quickly converted the mistake into a 31-yard field goal by Lawrence Tynes.

And with that, a Candlestick Park crowd practically willing its team to the Super Bowl went silent and the 49ers' improbable season was over.

"It's tough when you're that close to your ultimate goal and you fall short," safety Donte Whitner said after the 49ers' 20-17 loss in the NFC Championship Game. "It's not the end of the world, but right now it feels like that."

Whitner and his teammates were quick to point out that they didn't blame Williams for the defeat.

The 49ers' defense, which was picked apart by Giants quarterback Eli Manning and wide receiver Victor Cruz in the first half, toughened in the second half and kept giving the offense chances to win the game in regulation and overtime.

The 49ers' offense, however, could not summon the magic that won the divisional-round game over New Orleans.

The two heroes from that game, quarterback Alex Smith and tight end Vernon Davis, hooked up for two long touchdown passes against the Giants, including a 73-yard score in the first quarter.

But the offense finished the game with four straight three-and-out series and, worse, converted only once on third down.

Asked what he made of Williams' fumbles, Smith said there was plenty of blame to go around.

"I'm looking at it from – what did we go? One of 13 on third downs?" Smith said. "He didn't lose the game. We lost the game across the board."

A quick whistle by officials late in regulation also is likely to haunt the 49ers during the offseason. The controversial call wiped away a potential fumble recovery deep in New York territory that, had it not occurred, likely would have given the 49ers the lead late in fourth quarter.

The 49ers had forced 43 turnovers entering the game, and they had parlayed a simple formula – take the ball away more than you give it up – into victories throughout the season, including against New Orleans.

Against the Giants, however, the 49ers squandered their chances for takeaways.

One sure interception in the second half was undone when safety Dashon Goldson and cornerback Tarell Brown collided, leaving neither man with the ball and Brown with a head injury that forced him from the game.

From that point, the 49ers' top cornerbacks were veteran Carlos Rogers, rookie Chris Culliver and seldom-used Tramaine Brock.

A near replay of that missed chance occurred in overtime when Goldson and Rogers ran into each other trying to intercept another floating pass from Manning.

The most troubling, however, was the would-be fumble, which occurred at the end of a six-yard pass to New York running back Ahmad Bradshaw at the Giants' 21-yard line with 2:29 remaining. Before Bradshaw went to the ground, linebacker NaVorro Bowman stripped him of the ball, and the 49ers recovered.

Head linesman Mark Hittner, however, quickly ran to the middle of the field and ruled that Bradshaw's forward momentum has stopped and the play was blown dead before the fumble. The 49ers could not challenge the play in that situation, and the team's sideline, where the play occurred, erupted with disbelief.

"It looked like a fumble," coach Jim Harbaugh said. "Every play that happened in that game with the exception of that one was played out to the conclusion of the play."

What made it sting even more is that the 49ers were denied a similar takeaway when they beat the Giants 27-20 in the regular season.

"That's something we're still talking about," Whitner said. "It's a bang-bang play. The refs made the decision, but that's not the reason we lost the game.

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