Through the mid-1980s and most of the 1990s, a Saint Louis-Wai'anae matchup was a staple for prep football at this time of the year. Yet, it has been more than a half-decade since the two have met in postseason.

At 8 o'clock tonight, the top-ranked Crusaders (10-0) will take on the No. 5 Seariders (8-4) in a semifinal of the First Hawaiian Bank Division I State Football Tournament at Aloha Stadium. The winner plays for the state title Dec. 1 against the winner of the Kahuku-Baldwin semifinal earlier tonight.

Although the Seariders beat the Crusaders, 30-20, last year, it was in a nonleague contest. The last time they met when it really counted was in the 2000 state semifinal, which Saint Louis won handily, 63-0. It was the last of 14 consecutive wins by the Crusaders against the Seariders, half of them for O'ahu Prep Bowl titles. The average margin in those victories during that span was about 25 points.

But these are different times.

This Saint Louis team has a quarterback who can run.

"They just add another aspect to their offense," Wai'anae coach Danny Matsumoto said.

This Wai'anae team has a quarterback who can pass when needed.

"Running is their forte, that's what they're going to do," Saint Louis coach Delbert Tengan said. "If they can run, their play-action pass will be much more effective."

The quarterbacks — Saint Louis' Micah Mamiya and Wai'anae's Ben McQuown — both are juniors and both wear No. 7. Both give opponents fits.

The Crusaders' hybrid offense has features of the run-and-shoot and the option, both of which Mamiya has mastered. He has passed for 1,544 yards and 12 touchdowns and rushed for a team-leading 504 yards and nine TDs.

"It's kind of scary for us," Matsumoto said of Saint Louis' offense. "It just means we'll have to come up with different (defensive) schemes and, hopefully, we'll guess the right one (to use)."

The Seariders run effectively and have an army of running backs to ensure fresh legs from the first through fourth quarters. But as Kealakehe learned in a 28-14 opening-round loss last week, if you stack the box for the run, McQuown will hit his receivers, as he did with three touchdown passes against the Waveriders.

The Seariders have rushed for 2,387 yards, but McQuown has kept defenses honest by passing for 1,058 yards and nine TDs.

"McQuown makes plays," Tengan said. "He scrambles well, buying time and making plays. You gotta defense both (the run and pass), no doubt about it."

McQuown will dump passes off to his running backs, like Justin Kauwalu, Danny Kekoanui and Joe Abell. But when he hits his wideouts, it's usually for big chunks of yardage. Don Medeiros, Nathan Malaki and Miller Ualesi average 26.4, 27.4 and 19.0 yards per reception, respectively.

Ironically, both teams have defensive personnel to neutralize the offenses they face.

Wai'anae's defense swarms to the football. That was perhaps its biggest key to containing Kealakehe running back Gabe Tuata to 29 yards rushing last week. Tuata sometimes spun off the initial hit, only to be met by more tacklers converging on the play.

The players in on nearly every play are linebackers George Kauwalu, Chad Duran and Kaipo Punihaole. They are seemingly never blocked.

"They've been playing solid defense," Tengan said. "First downs will be hard to come by."

Wai'anae allowed only two touchdowns in three games of the O'ahu Interscholastic Association tournament. It beat 'Aiea, 46-0, and Mililani, 7-6, and lost 7-0 to Kahuku. It gave up two in last week's 28-14 win against Kealakehe.

The Crusaders have an agile defensive front with Ryan Eastman and Geordan Hanohano at tackles and Scott Smith and Solomona Aigamaua at ends. They also keep middle linebacker Jacob Barit free to roam.

"We watched the Kamehameha (game) tape," Matsumoto said of the Saints' defensive front. "They manhandled people up front. They're very strong up front.

"The key for us is to maintain our blocks."

Reach Stacy Kaneshiro at skaneshiro@honoluluadvertiser.com.