L.J. Alofaituli grimaced as he struggled to catch his breath. 

No, this wasn’t out of fatigue after he and his Sierra football team were pushed for four quarters for the first time this season.

It was out of pure emotion after the Timberwolves upended visiting Central Catholic 17-14 at Daniel Teicheira Memorial Stadium.

“This is overwhelming,” the Sierra defensive end said. “This proves that Sierra isn’t about just winning against easy teams. We showed that we’re also a team to beat in this league, and we’re going to bring it every time.”

And four full quarters, too.

Sierra, one of two remaining unbeaten teams in the Valley Oak League at 5-0 overall, hadn’t been challenged up until this point. In its first four games, all blowouts, the starters were sidelined while with running clocks during fourth quarters.

The Timberwolves matched the state’s two-time defending small-school division champion hit for hit from whistle to whistle. They ultimately came up with more big plays on both sides of scrimmage in what 10th-year coach Jeff Harbison called “one of the greatest victories in the history of Sierra High School.”

“I looked at the eyes of the kids at halftime and that said it all,” Harbison said. “They said they were going to play four quarters of football. They know that people doubt them. Well, we got tested tonight and we came out on top.”

Hunter Johnson made the play of the game to put Sierra ahead for good with 6:29 remaining. On third and goal, the 6-foot-4 receiver used his wingspan to tip a Devin Nunez pass to himself with one hand, and as he regained his balance Johnson hurdled a grounded defender at the goal line to complete the 6-yard touchdown.

“I saw it hit my hand and I just had to watch it the whole way in and stay focused,” Johnson said. “You can’t be worried about getting hit or anything, just bring the ball in.”

His natural instincts and athletic ability took over from there.

“Honestly, I don’t know how that happened,” Johnson said.

He made it happen throughout the deciding drive. Sierra had a first-down catch by Johnson negated by a personal foul, forcing a second-and-31 situation. Nunez (12 of 18, 141 yards) delivered a 51-yard strike to his big target and later completed a 14-yard pass to him on third and 13.

“It doesn’t matter if the ball is in my hands or not, I know that the team is going to be able to make plays,” Johnson said. “We play as one unit.”

Sierra’s stout defense held on Central Catholic’s final drive, which started on its own 10-yard line and used up 15 plays — including two fourth-down conversions — to reach the Timberwolves’ 33. On fourth and 12 with 12 seconds remaining, touted tight end Jared Rice could not come down with the ball as Hunter Petlansky slung it to him down the right sideline.

Harbison spent his final timeout to settle the troops after their raucous and much-deserved celebration. Sierra’s final play from scrimmage was a kneel-down from Nunez, leaving the Timberwolves’ vaunted rushing attack with just 10 second-half yards and 94 total. Mark Paule Jr. (19 rushes, 95 yards, TD) failed to reach the century mark for the first time, but on this night the defense — led by hard-hitting linebacker Trevon McCray — took center stage.

The Raiders (1-1, 3-2) came up empty handed on three trips inside Sierra’s 35-yard line.

“The defense made a great statement tonight with their never-say-die attitude,” Harbison said. “We had some things go against, but they hustle and they get to the ball.”

The Timberwolves didn’t allow Petlansky to get comfortable in the pocket. His 60-yard touchdown pass to Jacob Days tied the game at 7-7 late in the first quarter, but he was otherwise off the mark on most of his throws. The 6-3, 225-pound standout completed just seven of 19 passes for 130 yards. He also rushed for 30 yards but was knocked for big losses on sacks by Andrew Guevara and Alofaituli.

During Central’s last-ditch effort, Sean Murray sacked Petlansky and jarred the ball loose on second and 10. The Raiders recovered the fumble near their own sideline for a 2-yard loss.

“(Sierra’s pressure) created problems at times but it also opened up opportunities to scramble and make big plays,” Petlansky said. “It was give and take.”

No team has had it tougher than Central Catholic to open VOL play. In their first game back in the VOL since the late 1970s, the Raiders needed a breakout performance and 2-point conversion from Justin Rice to squeak out a 29-28 overtime win over defending champion Manteca.

Rice overcame a slow start Friday and finished with 115 yards rushing, 58 receiving and a touchdown.

“There are great teams in this league,” Petlansky said. “Pretty close games so far that came down to one or two plays.”