LARAMIE, Wyo. — In the dark under the grandstand, he waited.

The Cal Poly football team filed out of Wyoming’s War Memorial Stadium, poised to celebrate its biggest victory in the Tim Walsh era, and Mustangs athletic director Don Oberhelman sprang into action.

As the team approached the tunnel leading to the locker room, Oberhelman leapt, twisted in mid-air and smacked backs with sophomore cornerback Jordan Williams, who had pulled off the same acrobatics.

If that moment didn’t convey the significance of Saturday’s 24-22 upset over the Cowboys —Walsh’s first over an FBS program since taking over at Cal Poly in 2009 —there’s no way words could do it justice.

The Mustangs’ fourth-year head coach was asked to anyway.

“The significance is it kind of validates that you’re a good FCS school,” Walsh said. “Because I think the quality FCS schools across the country can compete against certain FBS programs.

“There’s nine games left. I’m not going to put too much on this. Today, we’re going to celebrate this win. It’s a great win for Cal Poly, and a great win for the program and the people that played the game for us, but the bottom line thing is we gotta come back and play well a week from now or it doesn’t matter.”

Cal Poly followed a Hollywood script. The Mustangs jumped out to a two-touchdown lead. They lost it, along with all of the momentum. Then when crunch time hit, they pulled it out and held on.

To make it sweeter, the Mustangs beat a program that hadn’t lost to an FCS program since the subdivision was established as Division I-AA in 1978. Wyoming was 9-0 against the FCS since 2000.

Senior cornerback Nico Molino intercepted Wyoming quarterback Kolby Kirkegaard at the Cowboys’ 40-yard line with 1:37 left in the game, and Mustangs quarterback Andre Broadous knelt three times to preserve the two-point lead and the victory.

With 9:49 left in the game, Arkansas State transfer kicker Bobby Zalud nailed a 51-yard field goal on 4th-and-3 from the 34, and that proved to be the winning score.

“As soon as I kicked it, I knew it was good,” Zalud said.

“I feel like if coach has the confidence in me, I definitely have the confidence to go out there. I feel confident to hit 60 plus.”

It was the first FBS upset for Walsh in six tries. The Mustangs took a 9-0 lead at San Jose State in his first season in San Luis Obispo but eventually fell 19-9 in that game and hadn’t come close to beating an upper subdivision team since.

In their only chance to upset an FCS program this season, the fifth-year seniors pulled it off on their last try.

“It’s huge to do it with this coaching staff,” said senior linebacker Kennith Jackson, who redshirted in 2008 when Cal Poly last beat an FCS team — San Diego State, 29-27. “Since they came in, we haven’t gotten that win. It means a lot to not only me but everybody back at home. It means everything to the community to know they have a team, and their team’s here to play.”

Senior running back Deonte Williams had a 65-yard touchdown run, a career long, on Cal Poly’s first possession and set up another score with a new even longer 74-yard run on the next drive.

Kristaan Ivory finished the possession with a 9-yard touchdown run a few plays after Williams ran out of breath and was caught from behind on the 5-yard line.

Williams finished with 187 yards on 19 carries, a Cal Poly best but not a career high. Williams had 194 yards on 22 carries against Idaho as a true freshman for Northern Arizona in 2008.

He transferred to Sierra College the following season, spent a year on the sidelines after a transfer to San Diego State fell through and landed at Cal Poly last year, where he waited for carries behind fullback Jake Romanelli, slotback Mark Rodgers and Broadous.

Molino played with Williams at Northern Arizona before he himself transferred to Cal Poly as a sophomore. “The day he said he was coming here, I told everyone watch out for Deonte,” Molino said. “He’s going to kill it this year. He’s going to break run after run after run.

“As you saw tonight, he ran all over their defense and he’s going to do it every single game from here on out. It’s not even a question in my mind.”

Ivory would score another touchdown on a 5-yard pass from Broadous to give the Mustangs a 21-15 with 4:57 left in the third quarter.

That score came after a lengthy stretch where the Cal Poly offense had been almost completely ineffective moving the markers.

After the Mustangs took the two touchdown lead, things stagnated. At the half, Williams had 162 yards. The rest of the team had 82. After the first two touchdowns, Cal Poly went six scoreless possessions without advancing the ball into Wyoming territory.

Wyoming used a 37-yard punt return by Jalen Claiborne to set up its first touchdown, a 1-yard rushing score by Shaun Wick. The Cowboys got the two-point conversion, and Wick had another 1-yard TD run to give Wyoming a 15-14 lead going into the half.

Wick, a former St. Bonaventure High standout, ran for a team-high 64 yards and scored all three of the Cowboys’ touchdowns.

But Zalud turned the momentum back to the Mustangs on a 62-yard punt that was downed at the Wyoming 15 yard line and completely flip-flopped the field position.

After a quick three-and-out by the Cowboys and a 14-yard punt return by Chris Nicholls, Cal Poly started its next drive at the Wyoming 40.

Broadous’ pass to Ivory on third-and-goal from the 5 gave the Mustangs back the lead, and Zalud clinched it on Cal Poly’s most methodical drive of the game.

On a possession that started at their own 14, the Mustangs went 52 yards in 14 plays, culminating in a fourth-and-3 from the Wyoming 34.

With a seven-point lead and less than 10 minutes left, Walsh said there was no thought about punting. Cal Poly was either going to go for it or let Zalud kick the field goal.

The 51-yarder was the longest in his two-game tenure with the Mustangs. Zalud also had a 56-yarder with Arkansas State, but in a blowout victory over Memphis, that kick was just a passing footnote. This one had game-winning pressure built in.

“I’ve said it all along, we got a good football payer in Bobby Zalud,” Walsh said. “To kick a 51-yard field goal with that kind of pressure in this environment, it was a big kick.

“We were either going to go for it or kick it, and I know he’s that good. We practiced in Cheyenne, and he was kicking 64- and 65-yard field goals. This 7,000 feet everyone thought would hurt us, it might have helped us tonight because that 51-yard field goal was in the altitude.”