First Matt Cooper had to wait two extra days.

Then a rain delay postponed Saturday night’s season finale by 39 minutes.

Once he finally stepped on the mound for his last collegiate start, the Hawaii right-hander wasted no time joining an elite group of pitchers in the Rainbow Warriors’ 5-1 win over UC Riverside.

Cooper, who needed five strikeouts to become the 14th pitcher in school history to reach 100 in a single season, got it by the third inning and finished with 11 to get to 106 for the year.

He passed Chuck Crim for 13th on the school’s single-season list and left to a standing ovation from the Les Murakami Stadium crowd of 1,860 with two outs in the top of the eighth inning.

Cooper (6-5) got the win to finish over .500 for the season. He gave up seven hits and three walks to finish the year with a 1.60 ERA.

It’s the lowest ERA by a starting pitcher in a season since Derek Tatsuno in 1978 and the ninth-lowest ERA by any UH pitcher to throw at least 20 innings in a season.

Hawaii (22-31, 6-18 Big West) ended its season with its second series win in conference play.

Catcher Tyler Young, one of 10 seniors who dressed for the final time in a UH uniform, had a career-high three hits and drove in two runs.

Marc Flores went 2-for-3 with an RBI double and Kaeo Aliviado went 2-for-3 with two runs and an RBI to finish the season hitting .310.

Cooper threw at least seven innings in nine of his 14 starts this season and finished his career with a 1.78 ERA in 121 2/3 innings at home.

UC Riverside (26-28, 12-12) scored its only run in the top of the fifth on a wild pitch by Cooper, who hurt himself earlier in the inning running to field a UCR bunt.

After a quick meeting with coach Mike Trapasso and a trainer, Cooper threw a few warm-up pitches and stayed in the game. He struck out Cody Hough with runners on second and third for the second out before a wild pitch scored Francisco Tellez from third.

Aliviado saved two runs with a diving catch in center for the final out. Cooper came back out for the sixth. He retired eight of his final 12 batters to finish off a 128-pitch effort.

Andrew Jones replaced Cooper and got Tellez to fly out to left to strand two Highlanders on base.

UC Riverside starter Ben Doucette (3-6) was tagged for five hits and three runs in 2 2/3 innings to take the loss.

Stephen Ventimilia started the game with a leadoff walk and Conner George doubled him in to give the Rainbow Warriors a 1-0 lead.

UH added two runs in the third on RBI singles by Aliviado and Young.

Aliviado led off the seventh with a base hit and scored on a double by Flores, who took third on a throwing error.

Young drove him in with a two-out RBI single to make it 5-1.

UC Riverside made one last charge in the ninth as Drake Zarate and Matthew Ellis led off with singles. UH brought in junior Eric Gleese, who gave up an infield single to load the bases with nobody out.

Gleese struck out pinch hitter Mark Contreras swinging and caught Joe Chavez looking for the second out. Devyn Bolasky grounded out to third to end it.