STANFORD, Calif. -- For almost eight months, Jordan Williamson shouldered the responsibility for sending Andrew Luck and an elite class of Stanford seniors out with a Fiesta Bowl loss.

With the program unable to lean on Luck anymore, Williamson booted back all the blame that would've came the Cardinal's way on his rejuvenated right foot.

Williamson kicked a career-long 46-yard field goal and the go-ahead score from 20 yards, saving No. 21 Stanford in a 20-17 win over San Jose State on Friday night in its first game since Luck's departure.

"I feel like I finally put everything from the past in the past and now I can focus on the future," a smiling Williamson said. "It was a tremendous feeling."

Williamson, who missed three field goals -- including a potential game-winner in regulation -- in a 41-38 overtime loss to Oklahoma State on Jan. 2, might have been the only one with a reason to hold his head down following that fantastic effort from both sides.

Now he might be the only Stanford player who should hold his head high after a shaky start this season.

Former backup Josh Nunes threw for 125 yards and a touchdown in his first start in place of Luck, the NFL's No. 1 overall draft pick. While the redshirt junior finished 16 for 26 with no interceptions, he struggled to move the offense when it counted and it almost cost the Cardinal (1-0) dearly.

"We were close to doing a lot of really good things tonight," Nunes said. "But close doesn't always win football games."

It usually loses them.

The David Fales-Blake Jurich quarterback combo gave Stanford fits until De'Leon Eskridge fumbled in Spartans (0-1) territory late in the third quarter. That set up Williamson's tiebreaking kick, giving the redshirt sophomore a small stroke of redemption after months of public silence and tissues and tears back home.

"That shows the kind of person he is," said Stanford's Stepfan Taylor, who ran for 116 yards and a touchdown. "That's a lot of pressure, and missing them in the Fiesta Bowl you know all the pressure is going to be on him. He's cold-blooded."

So was San Jose State's passing game.

Fales threw for 216 yards with one touchdown and an interception that landed in the hands of Ed Reynolds with 71 seconds remaining to seal Stanford's victory. Jurich ran for 32 yards and a score.

The fight Stanford showed so many times behind Luck dissolved.

With the two-time Heisman Trophy finalist now with the Indianapolis Colts, the Cardinal converted only 2 of 13 third downs (although it was 2 for 3 on fourth downs) and allowed the Spartans to move methodically at times down field. San Jose State outgained Stanford 288 to 280 total yards.

Stanford beat San Jose State 57-3 last year and has won five straight meetings.

"Since we got our butts kicked here last year, we could have won every game since," third-year San Jose State coach Mike MacIntyre said. "So we're making progress. We're getting bigger, stronger and faster. We're making strides. But in no way, shape or form is this a moral victory. We're a better football team, but we have to finish it off."

Taylor ran for 38 yards almost untouched until a defender tackled him on the game's first drive. Remound Wright converted a fourth-and-1 from the 10-yard line, and Taylor dived over the pile for a 1-yard TD on fourth down to give Stanford a 7-0 lead.

Nunes quickly led Stanford down field again and tossed a perfect ball in the corner on a stop-and-go route by Drew Terrell for an 11-yard score and his first career touchdown pass.

The first-game hiccups eventually surfaced, though, and bubbling later than expected until they almost completely popped Stanford's season.

Game-clock management became an issue on Stanford's final drive of the first half, tossing a short pass over the middle to tight end Zach Ertz, then throwing incomplete and running on third down to settle for a field goal. Williamson, who tore a groin muscle last October and was never the same when he returned, made his career-high 46-yarder as time expired to extend Stanford's lead to 17-3.

"He's healthy, he's confident and he's kicking the ball well," Stanford coach David Shaw said.

Added Williams: "I was excited that the coaches threw me out there and let me hit it. Distance was not an issue."

All the same problems that plagued the Cardinal defense in losses last year to Oregon and Oklahoma State -- no cornerback coverage, poor open-field tackling and quarterback pressure when it counts -- looked even worse with two new starting safeties.

Jurich ran for a short touchdown on San Jose State's first possession of the third quarter and Fales floated a 21-yard touchdown pass to Noel Grigsby to tie the score at 17-all late in the third quarter.

Fales, who transferred from Monterey Peninsula Community College in the spring, redshirted at Nevada in 2009 but quickly had San Jose State in position for the season's first shocking upset.

One mistake ended all that.

Reynolds stripped Eskridge on a pitch play, and Usua Amanam recovered the fumble at San Jose State's 38-yard line. Stanford's offense stalled again, and Williamson made his second field goal.

San Jose State stuffed Taylor on fourth-and-1 with fewer than 7 minutes to play, sending MacIntyre jumping and high-fiving all over the sideline and on the field. Fales and the offense failed to even get a first down on the next two possessions and Reynolds stepped in front of his final pass to close out San Jose State's rally.

San Jose State, which went 5-7 last year after posting a 1-12 record in 2010, has not beaten a ranked team since a 27-24 win over No. 9 TCU at Spartan Stadium on Nov. 4, 2000. They're winless against 20 ranked teams since.

"It was real close," Taylor said. "But close will get you beat in a heartbeat."