Hawaii required one of its best performances of the season if it was to top Illinois State in the first round of the Hawaiian Airlines Diamond Head Classic on Thursday. Instead, the Rainbow Warriors submitted their worst in years.

The Redbirds of the Missouri Valley Conference walloped the ’Bows 71-45, sending the crowd of 4,146 out into the winter night for comfort, for there was little to be found in the Stan Sheriff Center.

One year to the day after the NCAA laid bare its severe sanctions against the program — you know them well at this point — the overwhelmed and overmatched ’Bows (4-6) had nowhere to hide on national TV.

“Probably one of the worst performances in that arena, in this event, we’ve seen,” UH coach Eran Ganot said after a long pause at the postgame interview podium. “I think the people in Hawaii deserve better.”

UH’s point total was its lowest since a 59-44 loss to Idaho on Jan. 6, 2011. UH set a Diamond Head Classic mark for field-goal futility with only 14 makes in 55 attempts, and for percentage, 25.5 percent shooting was a season worst.

Phil Fayne dunked UH into oblivion in the second half, throwing down three jams during an 18-0 run that blew a reasonably close game into 30-point territory until the buzzer mercifully sounded.

“We got punked,” Brocke Stepteau said.

The point guard pointed out a telling second-half play in which Illinois State had to throw up a desperation 3 on an inbounds pass with one second on the shot clock. The Redbirds missed the heave but outhustled UH for the predictable rebound when the Rainbows failed to box out.

“That play told the whole story,” he said.

Two weeks off since two losses in the Pearl Harbor Invitational apparently did little good. The three-game losing streak is UH’s longest since it dropped four to end the 2012-13 season.

“We’re just embarrassed at how we performed tonight,” forward Noah Allen said. “There’s really nothing else to say. We played terrible and let the fans down, ourselves down, the coaches down. The good thing is we have another game (today). We can’t let that happen again.”

UH is in the consolation bracket for the first time in three years. It now faces a daunting task against Utah of the Pac-12 at 7:30 p.m. in an ESPNU-televised game.

The Utes lost their best player, forward Kyle Kuzma, to an ankle sprain in the first minute of their game against San Francisco and lost 89-86. They nearly overcame the injury behind 35 points from guard Sedrick Barefield.

“They’re not going to feel sorry for us,” Stepteau said.

For Illinois State (7-3) it represented a breakthrough after the Redbirds coughed up late leads in three previous road games, all losses. ISU takes on San Francisco in today’s second semifinal at 5 p.m.

“We didn’t come here to win a game, but to win the tournament,” Redbirds coach Dan Muller said. “Our guys were locked in. We talked a lot about staying focused with leads.”

For Hawaii, calling it a setback didn’t do it justice.

Stepteau, Gibson Johnson and Allen led UH with 10 points apiece. Allen’s 4-for-13 shooting somehow represented a bright spot.

Allen had a 3-pointer waved off for a travel, then ISU kicked off the run with back-to-back 3s.

“I think our team is pretty fragile. That’s something we keep going through,” Ganot said.

Fayne (14 points) hit the ’Bows with a putback jam for a 56-33 lead with 10 minutes to play, and it felt like a finishing move. He followed it with an alley-oop baseline slam from point guard Paris Lee.

Forward Deontae Hawkins led the Redbirds with 16 points.

ISU scored the game’s first 10 points and took an eight-point lead into halftime. The Redbirds scored on their first four possessions of the second half to build their largest lead to that point.

UH missed its first six shots and fell behind 10-0 in a blink, battled back to within three, but never totally dug itself out of the hole.

Jack Purchase missed all of his seven shots in the first half and UH shot 23.3 percent in the period.

San Francisco 89, Utah 86

Ronnie Boyce scored 19 points off the bench, Chase Foster and Remu Raitanen added 12 points apiece and the Dons (9-2) held off the Runnin’ Utes (7-3).

Tulsa 74, Stephen F. Austin 51

The Golden Hurricane advanced to the semifinals thanks to a strong effort from their reserves, who outscored the Lumberjacks’ bench 42-15.

Pat Birt led Tulsa (6-4) off the bench with 20 points on 6-for-7 3-point shooting.

San Diego State 66, Southern Miss 51

The Aztecs, the 2012 DHC runners-up, pulled away late in their quarterfinal after the Golden Eagles made it a game — USM clawed to within five points with 12 minutes left.