CONCORD -- Justin Alumbaugh jumped in celebration as De La Salle running back John Velasco broke off a long touchdown run on the Spartans' second play of the game.

Though there weren't too many more smiles on the De La Salle sideline for the rest of the opening half, the Spartans made Alumbaugh a 34-14 winner in his head coaching debut Friday against visiting Clayton Valley Charter at Owen Owens Field.

In a season opener between defending North Coast Section champions, Division II Clayton Valley hung tough with Division I De La Salle before the Spartans eventually pulled away.

"We played hard, but I don't think we played well," Alumbaugh said. "We made a lot of mistakes. Every time we tried to take a big shot on offense we'd fumble or we missed an assignment on the offensive line, a dropped pass here or there."

De La Salle High’s new head coach, Justin Alumbaugh, left, starts the season with ex-head coach Bob Ladouceur, right, by his side against Clayton
De La Salle High's new head coach, Justin Alumbaugh, left, starts the season with ex-head coach Bob Ladouceur, right, by his side against Clayton Valley Charter High in their high school football game played at De La Salle High School in Concord on Aug. 30, 2013. (Dan Honda/Staff)

Alumbaugh's debut as De La Salle's head coach marked the first time in 35 years that someone other than Bob Ladouceur was calling the plays. Ladouceur was still on the sidelines, though, constantly talking with Alumbaugh and the rest of the coaching staff.

The Eagles trailed by just a touchdown at halftime, putting together long drives and converting on chancy fourth downs. Clayton Valley tied the score at 7-7 late in the first quarter on Miles Harrison's 10-yard scoring run, though the Spartans immediately took the lead back when Jerek Rosales returned the ensuing kickoff 96 yards for a touchdown.

The large Clayton Valley contingent erupted again when Kristian Mamea caught a 13-yard touchdown pass from Gabe Taylor to pull within 21-14 just before halftime.

But that was as close as the Eagles got.

De La Salle tightened up its defense, outscoring the Eagles 13-0 after the break as Dasmond Tautalatasi came up with two second-half interceptions.

Velasco impressed in his first start for De La Salle. With Tautalatasi dinged up and playing both ways, Velasco made the most of his increased workload, rushing for 184 yards and three touchdowns on 18 carries.

"He's in better shape, he's stronger," Alumbaugh said of Velasco. "He's been running like that for a few weeks and really worked hard in the offseason."

Clayton Valley's Harrison was also productive, tallying 175 rushing yards and a touchdown on 24 carries.

Clayton Valley coach Tim Murphy, using a new quarterback in Taylor and a new running back in Harrison, thought his team made a statement with its effort against the vaunted Spartans. He just wished the Eagles had tackled better.

"It's a great learning experience any time you play a team of this caliber early in the season," Murphy said. "And I think that we did relatively well against them shows what kind of team we have."

Murphy is also worried that he lost Mamea, the Eagles' tight end, to a broken leg. Mamea was injured on a hit well behind the ball on one of Tautalatasi's interception returns.

Assistant coach Ladouceur

Read how Bob Ladouceur adjusted to his first game as an assistant coach with the De La Salle High football team at www.contracostatimes.com/high-school-sports