They started out as rivals, 30 kids spread out across a handful of teams in the Spring Lake Park football association. They played against each other for third-grade bragging rights.

“Our coaches came together and said, ‘You guys, stop fighting, you’re going to play together one day,’ ” Lamari Brown said. “It took us a while to get there, but we’re here now.”

Those 30 kids are now high school seniors living out their childhood dream together as a brotherhood. The Spring Lake Park Panthers are headed to the Prep Bowl.

Led by their core of seniors, the Panthers rode a punishing running game, swarming defense and aggressive coaching decisions to advance to the Class 5A championship game with a 39-23 victory over St. Thomas Academy on Friday in a battle of undefeated teams at U.S. Bank Stadium.

Spring Lake Park will face the winner of Saturday night’s semifinal between Elk River and Chanhassen.

The Panthers won four games last season. Now they are 12-0 and stand one victory away from claiming the second football state title in school history.

“We knew we were better than four wins,” quarterback Nolan Roach said. “We lost some games we definitely should not have lost, and that just kept us hungry this offseason and allowed us to play with a different kind of intensity.”

That intensity was on full display in the semifinals, highlighted by an avalanche of big plays in the third quarter that swung momentum squarely in their favor. A pick-six by Marcus Snyder, a successful onside kick and two quick offensive touchdowns staggered the Cadets.

“There’s a reason they’re 12-0,” St. Thomas Academy coach Travis Walch said.

Two main reasons: Brown and Roach, a dynamic duo that should be called “Hammer and Snake.”

Brown hits like a hammer when he takes a handoff. Roach slithers through the defense when he keeps the ball on the option.

Together, they combined for 329 yards rushing and four touchdowns.

“It’s difficult to take both away,” Panthers coach John Stewart said.

Or either. Brown is a powerful back who commands full attention from the defense. Time and again, Roach faked a handoff to Brown up the middle and the St. Thomas Academy defense converged on him, enabling Roach to slip around the edge on the keeper. He rushed for 190 yards on only 15 carries.

“It’s great to have a guy as dynamic as Lamari,” Roach said. “He’s got all 11 [defenders] keying on him. It makes my job really easy.”

The Panthers rushed for 402 yards total against a defense that allowed an average of 78 yards rushing per game this season. The rushing total ballooned thanks to Stewart’s ultra-aggressive coaching decisions.

He called a fake punt at his own 29 on fourth-and-1 in the second quarter. The play gained 15 yards.

He called for an onside kick after Snyder’s pick-six early in the second half. That was successful, too.

Stewart also went for it four times on fourth down, converting two of them.

“In a game like this,” he said, “you’ve got to take some chances.”

Especially with a team that has put in the work to earn that trust. The senior class is the program’s largest in a long time, Stewart said. Those 30 seniors have grown up together and made a commitment to each other after a 4-6 finish last season.

Stewart noticed something different during winter workouts. The focus and attitude were sharper. That carried into summer conditioning.

“Everything became about doing all the little things right,” Stewart said, “and then momentum just kept building.”

That momentum looked like a runaway freight train in the second half Friday. The running game hummed. The defense played fast and physical. A spot in the Prep Bowl was not going to be denied.

This journey began 10 years ago for those 30 seniors, back when they were new to the sport and splintered into different teams. They couldn’t have possibly known where that beginning would lead, but here they are, together like their third-grade coaches predicted and on the doorstep of achieving something marvelous.