Hawaii seized upon a foul-fest of epic proportions, then seized the day from Cal Poly.

The Rainbow Warriors paraded to the free-throw line and overcame a slow start against a conference nemesis to claim their Big West opener for the first time in three years, 86-73, on Wednesday night at the Stan Sheriff Center.

A crowd of 4,319 saw UH make 34 of 42 free throws (81 percent) and improve to 12-2 overall on the season with their fourth straight victory. The makes and takes at the line were season highs.

The game was tied at halftime but Eran Ganot’s ’Bows steadily pulled away in what was a disjointed battle because of the constant whistles. There were 51 fouls called, including 30 on the Mustangs (6-8, 0-1).

“I said this at the half: composure,” Ganot said. “That’s going to be the biggest thing for our team every night, and I think we’ve come a long ways there.”

UH is now off to its best start to a season since its last time making the NCAA Tournament, the 2001-02 squad that opened up 15-2. The Rainbows host UC Santa Barbara (6-7, 0-0) on Saturday to cap a 10-game homestand.

Point guard Roderick Bobbitt led UH with 21 points, including a 12-for-14 effort at the line. He put it away in the final minutes once Poly went to fouling, making five of six.

Wing Aaron Valdes scored 20, going 9-for-10 at the stripe, and forward Stefan Jankovic had 19 points and 13 rebounds. Guard Isaac Fleming scored 12 with five assists.

Behind Jankovic and forward Mike Thomas, UH won the rebounding battle by 12 over typically physical Poly. Thomas grabbed a career-high 13 boards, including five on the offensive end.

“I was just tired of people viewing us as soft. That was the kind of like the thing with Cal Poly every year, they bullied us,” Jankovic said. “So we made sure we were gonna rebound.”

The Mustangs (6-8, 0-1) were Hawaii’s opening league opponent for the third time in four Big West seasons, and for the third time in a row. They won the last two, including in overtime at the Sheriff in 2015. It looked like another typical Poly game early as the visitors roared to a 14-5 lead.

“What you saw is what you’d expect in conference play,” Ganot said. “Intense.”

The ‘Bows climbed back into it behind Fleming’s playmaking off the bench and some stellar baskets by Jankovic. Quincy Smith scored inside on a feed from Fleming to beat the halftime buzzer to make it 37-all.

After falling behind by a David Nwaba basket to start the second half, the Rainbows battled back. Jankovic stepped into a 3 to match UH’s biggest lead to that point, 48-42.

The Rainbows scored on five straight possessions to go up double digits for the first time, 61-51, on a basket inside by Stefan Jovanovic with 11:58 to play.

Poly guard Reese Morgan (team-high 17 points) narrowed the gap to five with a 3-pointer, steal and layup with under nine minutes to go. Taylor Sutlive followed it with a 3 in transition to narrow the gap to 66-64 with 6:50 to play.

UH built the lead back up behind Fleming, who knifed in for a layup and made an extra pass to Aaron Valdes for an open 3 on the next possession for a 75-66 advantage. Poly called for time with 4:10 to go. They’d get it to six on a Jaylen Shead 3 with 1:40 remaining, but no closer.

“I wouldn’t say difficult, I would just say another game of basketball,” Fleming said. “With a lot of fouls, basically.”

Bobbitt made his free throws to extend it back to 81-71, followed by two more from Valdes. Fleming secured the final margin with a fadeaway corner 3 as time was expiring.

The Mustangs had one player, Josh Martin, foul out, while four of their starters were saddled with four personals.

“We have to make the adjustment to how the game is being called,” Cal Poly coach Joe Callero said. “Now, Hawaii is one of the most aggressive teams in the conference, as far as driving the ball to the hoop. Hat’s off to (Jankovic) in the post. He was a monster tonight. … I thought Bobbitt was aggressive to the rim time to time there.”

He also credited UH with turning the game around once it started posting up Valdes, who had just five points at the break.