In an open-and-shut case, shortstop Jordan Donahue and reliever Alex Giroux helped the Hawaii baseball team produce Friday night’s 3-2 victory over Cal State Northridge at Les Murakami Stadium.

A crowd of 1,572 saw Donahue open the way, driving in all three UH runs. Giroux pitched five perfect innings to close out the Rainbow Warriors’ sixth victory in a row. Giroux struck out eight, including six in a row from the fifth through the seventh inning.

“There’s not the proper adjectives to describe what he did tonight,” UH coach Rich Hill said of Giroux. “Six strikeouts in a row, eight strikeouts total, didn’t give up a baserunner, and that’s a first-place team right there that can really hit. Stunning performance.”

By improving to 27-15 and 10-9 in the Big West, the ’Bows clinched a winning regular season with 11 games to go. The Matadors, whose nine-game winning streak came to a halt, fell to 28-15 and 14-5.

Down 1-0, the ’Bows loaded the bases with two outs in the second inning. Donahue then hit a drive that landed just in front of sprawling center fielder Jakob Simons. Catcher DallasJ Duarte and outfielder Sean Rimmer raced home on Donahue’s double.

With the score tied at 2 in the fourth, Naighel Calderon hit a leadoff double to left. One out later, Calderon tagged up and went to third on Elijah Ickes’ deep flyout to right.

Donahue’s second two-out hit of the game, a single to left, brought home Calderon with the go-ahead run.

“Both of those at-bats I was trying to put a good swing on the ball, and try to get those runs in,” Donahue said.

On the two-run double, Donahue said, “I didn’t think it was dropping. (Simons) kind of got a bad first step, and he kind of dove. I’m thankful he didn’t catch it.”

On the go-ahead single, Donahue said, “I was looking for something up. I tried to get a pitch to drive him in.”

That proved to be enough for Giroux, who entered at the start of the fifth in relief of Sebastian Gonzalez. In his second series-opening start, Gonzalez allowed six hits and two runs — only one of them earned — in four innings.

While Giroux enjoys being used in stress situations, he said it was a “fresh start” to be summoned between innings. “I got the top of the lineup and I was ready to roll from the get-go,” he said.

After inducing a lineout and groundout, Giroux fanned Simons to end the fifth and begin a string of six strikeouts in a row. He struck out the side in the sixth, then struck out Shunsuke Sakaino and Ben Griffin in the seventh. Mason Le’s flyout ended the strikeout streak. But Giroux had a strikeout in each of the eighth and ninth innings.

Giroux said he relied on a cutter, which was in the low 80s, to complement a sinker and fastball.

“I think the cutter has been the best it’s been all season,” Giroux said. “I was throwing it as hard as I could, and it was finding places where they weren’t touching it. And I was able to throw my sinker off that. I was able to get the outside corner, got a couple guys looking. I kind of had everything going. It was a good night.”

In the ninth, Duarte went from behind the plate to the mound to deliver a pep talk, essentially encouraging Giroux to have fun.

“Alex Giroux for president,” Duarte said. “That kid right there works hard. Effort’s there. Everything is there. He comes out here and competes. We can’t ask for anything more.”

Giroux said: “I love that guy. Greatest catcher I’ve ever had, probably ever will. All the props to him.”