It was instantly one of the great shooting performances ever seen at the Stan Sheriff Center, and against the Hawaii Rainbow Warriors in general.

Cal State Fullerton guard Kyle Allman’s game for the ages — 40 points, 16-for-19 from the floor — had the crowd of 5,778 transfixed in horror, unable to look away from UH’s 69-66 loss on Saturday night.

Allman, a rangy 6-foot-3 junior from Brooklyn, N.Y., came within a point of matching the building scoring record despite attempting just six free throws and making three. He was that good from the perimeter, sinking five of six 3-pointers and a series of long 2s.

In contrast, when CSUF’s Josh Akognon set the Sheriff mark of 41 (tied by BYU’s Chase Fischer in the 2015 Diamond Head Classic) in a nonconference game back in 2008, he did it through sheer volume, shooting 12-for-29.

Allman’s refusal to miss meant UH (13-6, 4-2 Big West) dropped from first to fourth amid a two-loss crowd led by Long Beach State (6-2), UC Santa Barbara (5-2) and UC Davis (5-2). The ’Bows, stung by a second Big West opponent shooting 60-plus percent on them in six games, now head out for games at UCSB and Cal Poly (1-6) on Thursday and Saturday.

UH, on most nights, prides itself on its defense. Not Saturday, when Allman and UH’s Mike Thomas (26 points) came out on fire. Thomas cooled off after scoring 20 by halftime. Allman didn’t, pouring in 21 after the break on 8-for-9 shooting.

“We’ve got an issue there. We’re not good defensively,” UH coach Eran Ganot grumbled afterward. “You’re only as good as your last game.

“He did hit some tough shots, but once you give a couple of lapses to a guy like that, he gets going,” he added. “It probably wasn’t until the last play of the game where we rotated and got it out of his hands. Until then, we were just seeing how hot he could get.”

On UH’s last possession, the Titans did a good job of taking it out of the mitts of Jack Purchase, UH’s top long-range threat who’d already hit three triples. Instead, UH got it to Drew Buggs on the right wing, who was forced into a difficult, contested look that fell well short.

UH’s 11-point second-half lead withered under Allman’s intense heat, as the ’Bows’ sublime offensive execution of the first half got sapped in a number of poor possessions late. He entered the night as the Big West’s third-leading scorer at 17.7 per game, and departed second at 18.8. He matched UC Davis’ Corey Hawkins (2013) for the most points scored against UH in Big West play. Texas-Pan American’s Marshall Rogers had the most ever against UH, 47, in 1976.

Allman averaged 7.4 points in five previous games against UH. He scored six points in both of his two previous trips to the Sheriff but was a totally different player in CSUF’s first Big West win in Honolulu. Sheriff Drammeh, his primary defender, had a front-row seat to the show.

“He’s a good player. Our guys that were guarding him, it’s a team cover and everything,” Thomas said. “We gotta take that personally, and I’m sure we did. We gotta face facts and get better.”

After Purchase’s tip-in with 3:51 left gave UH a 65-59 lead, the home team went 0-for-5 from the field, 1-for-2 at the line, and committed a turnover. CSUF closed the game on a 10-1 run, with Allman supplying six of those points.

“Basically I told Jackson (Rowe) that we have to make a push, that if he and I led the others would follow,” Allman said. “We made a couple of defensive stops and went from there.”

Rowe scored the go-ahead points on an easy transition layup when the Rainbows failed to get back on a missed jumper with 1:45 left.

“That was maybe the biggest play of the game,” Ganot said.

UH lost for the first time in six games this season decided by five points or fewer, and for the first time in 14 games after leading at halftime.

“Unlike us. I feel like every close game I’ve been in since I’ve got here to UH, (we’ve) come out with a victory,” said Gibson Johnson, who scored 10 but had four turnovers and missed a layup down the stretch. “It sucks to be on the other end, but we know that happens sometimes. We just gotta bounce back.”

The ’Bows were without guard Brocke Stepteau (finger fracture) for a second straight game despite Stepteau practicing all week. Ganot said he was a game-day scratch and “he’s close. He’s as day to day as you can get.”