The glaring similarity grouping the Cal Poly football team’s past three losses to rival UC Davis was simple: The Mustangs lost.

Saturday’s game started the same way last year’s loss did, with the Aggies surging to an early lead. Later, it felt like 2010, when UC Davis rallied for a one-point comeback victory on a last-minute touchdown pass.

But by the end, head coach Tim Walsh’s Mustangs felt something this team had never felt before — the weight of the Golden Horseshoe Trophy.

Cal Poly (3-0) overcame a two-score deficit to start the game and held on to an eight-point lead in the fourth quarter for a 28-20 victory over the visiting Aggies (1-3) in the Big Sky Conference baptism for both teams.

“It means everything to me and my teammates,” said fifth-year senior linebacker Kennith Jackson, who was an inactive member of the 2008 team that last beat UC Davis 51-28. “We hadn’t gotten this win in three years. It really sinks deep to come back and get it against these guys.”

Senior running back Deonte Williams ran 20 times for 188 yards and three touchdowns, junior fullback Akaninyene Umoh carried 12 times for 87 yards and a 51-yard touchdown run and senior cornerback Nico Molino had another game-changing interception after ending last week’s victory at Wyoming with his first of the season.

It was the third straight 100-yard game for Williams, and after nearly running for 200 yards against the Cowboys last week, UC Davis seemed focused on containing the former junior college transfer.

“They were calling out my number,” Williams said, “saying ‘10’s lining up right here,’ but like I told you before, it all starts up front. Those O-linemen, I love those guys, like really. They block their butt off for me.”

Since taking over as head coach at Cal Poly in 2009, Walsh had been winless against the Aggies and head coach Bob Biggs, who is coaching his 20th and final season in Davis.

Cal Poly blew second-half leads in both 2009 and 2010, with the second one coming after the Mustangs built a 20-0 lead.

Last season, the Mustangs were on a roll and still alive for a playoff spot before coming out flat in Aggie Stadium and falling short in the end.

In each of the past two years, UC Davis denied Cal Poly a chance at an at-large FCS playoff spot and an outright Great West Conference title. Walsh exercised some demons but seemed just as happy to be 1-0 in the program’s new conference, where the champion is awarded an automatic playoff berth.

“You’ve got to win at home in this conference,” Walsh said. “So this is a huge game, not just because it’s UC Davis and all those things, but it’s the first Big Sky game.”

The Aggies drove for a 39-yard field goal on their first possession, and after a quick Cal Poly possession, they struck again for a 67-yard touchdown pass on a fake end-around from Randy Wright to Corey Galindo.

The Mustangs’ aggressive defense worked against them on that play, and after Cal Poly watched a 28-yard field-goal attempt by Bobby Zalud sail wide, UC Davis had the chance to push the lead to three scores.

Secondary coach Neil Fendall “is always telling us adversity is going to strike,” said junior safety Alex Hubbard, who was burned on the long touchdown in the first quarter, “and it’s how you respond. We responded right today.”

The Cal Poly defense held the Aggies scoreless on the next seven possessions. With nine players starting for the first time this season, the Mustangs’ defense continues to show it’s not the same group that was gashed by the pass last year, when it ranked next to last in the entire FCS.

“They fly around,” said Wright, who engineered each of the past two UC Davis victories in the Battle for the Golden Horseshoe. “They’re 11 men to the ball, going for strips and stuff. They’re aggressive. They’re well-coached.”

Even so, the Aggies were able to make it a game late, using a no-huddle offense that got them another 10 points.

Courtney Williams ran for a 2-yard touchdown, and Brady Stewart hit a 41-yard field goal.

When the Aggies got the ball back at their own 23 with 2:34 left, those who were around for the 2010 heartbreak were getting nostalgic.

But after UC Davis picked up one first down, Wright threw four straight incomplete passes, the last of which was broken up by Molino, and Cal Poly knelt three times before the students and band rushed the field to celebrate.

“This is a big game for them, too,” Walsh said, “and nobody quits in a big game. We had an opportunity to put them away and probably didn’t do it as good as we wanted to.”