SAN FRANCISCO >> Archbishop Riordan had five players on the floor against De La Salle in Tuesday’s NorCal Open Division boys basketball championship.

But in a stuffy, packed-to-capacity Crusader Forum in the heart of San Francisco, the hosts looked as if they had 10 defenders for most of their 52-40 victory over the Concord program.

After trailing 22-15 with 5:40 left in the second quarter, the Crusaders embarked on a 20-4 run over the next 11 minutes to blow the game open.

“We felt like we were not the most intense team in most of the first half, and our motto is to win the third quarter,” said center Nes Emeneke, who had three of his game-high four blocks in the eight-minute frame after halftime.

Emeneke, who stands 6-foot-10, and 6-9 JP Pihtovs shut down the paint, choking off De La Salle’s driving lanes and forcing the Spartans into tough shots.

Riordan led 42-26 at the end of the run.

A year after they lost to Salesian in the Open final, the Crusaders went on to hoist the program’s first Open Division trophy.

“It’s been a long time coming,” coach Joey Curtin said. “We’ve been knocking on the door for a long time.”

Up next is Roosevelt-Eastvale, which defeated powerhouse Notre Dame-Sherman Oaks 79-76 in the SoCal final. The teams will play Saturday night at Golden 1 Center in Sacramento for the state crown.

Andrew Hilman led Riordan with 15 points, and John Tofi gave the Crusaders a jolt of energy with 10 points. Oklahoma-bound Alec Blair, De La Salle’s all-time leading scorer, put in 16 in his final game as a Spartan, while David Patton scored 13 as De La Salle’s only other consistent scoring threat.

Texas A&M commit Jasir Rencher may have been quiet as a scorer, putting in just eight points, but he set the tone for the entire team with his willingness to guard his fellow future SEC player in Blair.

“Before the game, I told the team, ‘I don’t care if I score two or four points,’“ Rencher said, ”I knew what my assignment was, and I did my assignment, and we won the game.”

Riordan led 15-11 after one quarter, but De La Salle went on a 11-0 run to start the second period thanks to 3-pointers by Blair and Patton, two Patton free throws, and a David Balogun triple from the top of the arc.

After a Curtin timeout, the Crusaders went on a 8-0 run of their own. It was highlighted by a Tofi triple in transition and a spinning Kirby Seals layup through the heart of the De La Salle defense.

Right after two Rencher free throws gave Riordan a 23-22 lead with 30 seconds remaining in the first half, Blair made a spinning, twisting and impossibly difficult turnaround jumper to beat the buzzer.

“He’s a warrior,” DLS coach Marcus Schroeder said. “He played great, and gave everything he had.”

That was the last highlight for the Spartans, as Riordan outscored De La Salle 20-7 in the third quarter and then held the Spartans scoreless for the first four minutes of the fourth.

There was no doubt the Bay Area powerhouses were the two best teams in NorCal.

After so many close calls throughout the years, the Crusaders finally reached their first state title game since 2002.

Now Riordan will play against Roosevelt in the final game of the season.

“You know, it took me four years, but we finally got it,” Rencher said. “But we’re not done.”