Robert Siavii has been a big part of Leilehua's defense, and now the Mules find themselves in the state championship game.

Siavii returned a fumble for a touchdown and intercepted a pass that led to the go-ahead TD as second-seeded Leilehua defeated third-seeded Baldwin, 41-34, in the semifinals of the First Hawaiian Bank State Championship semifinals Saturday.

Leilehua (9-4) faces top-seeded Saint Louis (11-0) in the championship game Friday at 8 p.m. at Aloha Stadium.

"They always say defense wins championships," Leilehua coach Nolan Tokuda said. "It helped us win the OIA, and we hope we can take it up and win states.

"It carried us all season long and it's been more evident in the playoffs."

Siavii, a linebacker, returned a fumble 47 yards for a TD to put Leilehua ahead 20-13 with 2:39 left in the second quarter. It was the team's third straight score after trailing 13-0, and Tokuda said it was much needed to break Baldwin's momentum.

Siavii later intercepted a Baldwin pass in the third quarter that eventually led to the go-ahead score.

"The first half we had to adjust to their speed," Tokuda said. "Once we adjusted, we brought the heat and mixed it up pretty well."

The adjustments and big effort from the defensive unit helped contain Baldwin. Sophomore Kalua Ellis stripped the football that led to Siavii's fumble return and pressure from the defensive line led to Siavii's interception.

Tokuda said Siavii, co-captain with Peter Desaulniers, has had a bigger impact for the team off the field and during practice. A leader by example, Siavii is one of the first players to arrive at practice and makes sure everybody is ready to go.

"Everybody leans on each other and it just so happened he's in the position to make the play," with the support of his teammates, Tokuda said.

Reach Stanley Lee at sktlee@honoluluadvertiser.com.