WAILUKU » So much for the adage that the best offense is a good defense. In the case of Lahainaluna on Saturday night, it was an opportunistic defense that set the stage for an opening-round victory in the First Hawaiian Bank/HHSAA Division II football tournament.

Despite managing only 93 yards in total offense, the youthful Lunas capitalized on seven interceptions, a key fumble return for a touchdown and a safety for a 23-6 win over Konawaena before a modest crowd of about 600 fans at War Memorial Stadium.

The victory earned Lahainaluna a berth in Friday’s 7 p.m. semifinal game against second-seeded Waipahu.

The Lunas’ limited offense was spearheaded by freshman running back Jared Rocha, who rushed for a pair of touchdowns.

But it was Lahainaluna’s secondary that stole the show by repeatedly picking off Konawaena quarterback Kahoalii Karratti. The sophomore completed nine of 34 attempts for 108 yards.

In fairness, Karratti’s receivers dropped at least five passes in the game — including a pair in the end zone as the Wildcats closed the season with an 11-2 record. Lahainaluna improved to 7-4.

The Lunas led 14-6 at halftime despite managing only 16 yards in offense during the opening 24 minutes.

Lahainaluna struck first when Mark Alamon returned a fumble by Karratti 61 yards for a score early in the second quarter and freshman Amateo Flores converted the point-after for a 7-0 lead.

An interception by freshman safety Sione Filikitonga set up the Lunas’ second TD. He returned the ball 67 yards for an apparent score, only to have the play nullified by an illegal block. But Rocha bolted over from the 12, breaking a pair of tackles along the way, as Lahainaluna upped its lead to 14-0 with 9:42 left in the half.

Konaweana closed the gap to 14-6 when Karratti connected on a 12-yard scoring pass with Austin Dennis. A 2-point attempt failed.

The Wildcats threatened again as the half was coming to a close, but Filikitonga picked off a pass in the end zone.

Lahinaluna increased its lead to 16-6 when a slew of defensive linemen sacked Karratti in the end zone for a safety midway through the third quarter. The Lunas capped the scoring with a 4-yard run by Rocha with 45 seconds left in the game.

The loss overshadowed an exceptional performance by Konawaena senior defensive lineman Michael Andrade. The 6-foot-2 260-pounder was instrumental in shutting down Lahainaluna’s running game and put constant pressure on Lunas quarterback J.R. Kenolio-Doosenbery.