Mistakes here and mistakes there resulted in the Hawaii baseball team’s 4-3 loss to UC Riverside at The Plex in Riverside, Calif., on Sunday.

In losing twice in this three-game series, the Rainbow Warriors fell to 14-19 overall and 4-5 in the Big West. This season, the ’Bows have won two series, lost six and tied one.

For the ’Bows, this road game unfolded in parts. UCR right-hander Abbott Haffar turned a cameo appearance into a starting role. The Highlanders had announced they would “staff” the game, baseball’s vernacular for using multiple pitchers. Instead, Haffar pitched eight-plus innings, spacing nine hits but walking two and allowing two earned runs. Haffar, making his third start after 13 relief appearances, entered with a 4.54 ERA and 1.54 WHIP.

“He pitched well, and we weren’t able to score off him,” said UH coach Mike Trapasso, noting the ’Bows were scoreless through the first seven innings.

And when the ’Bows had scoring opportunities, they failed to maximize them. On Alex Baeza’s RBI single in the eighth, Maaki Yamazaki was thrown out on an attempted sprint from first to third. In the ninth, the ’Bows trailed 4-2 with Dallas Duarte at third and pinch runner Jack Kennelly on second. Scotty Scott lined a single to score Duarte, closing UH to 4-3, but Kennelly, who hesitated on the hit, was held at third. Kennelly was stranded when Yamazaki popped up and Baeza struck out to end the game.

“The story of the game is us not being able to score (early),” Trapasso said. “And late, when we’re trying to mount a rally, we make a couple mistakes — Maaki getting thrown out at third with no outs, and Jack Kennelly in the ninth, he goes back to the bag (at second initially) on a base hit. We had to hold him at third.”

There were earlier miscues that were costly. In the third, UH starting pitcher Logan Pouelsen intended to pick off Nathan Webb at first. But Pouelsen lost the grip on the move, and because he already was at the set position, he either had to hold on and accept the balk or risk throwing the ball away. He was called for a balk. Webb went to second, then scored on Taylor Juline’s ensuing RBI single.

With the bases loaded in the fourth, Pouelsen jammed UCR’s right-swinging Damien Sanchez with a fastball.

“He makes a great pitch, and blows Sanchez up,” Trapasso said. “But (Sanchez) hits it off his knuckles, just out of reach of Dallas at second base (to drive in two runs). You can get frustrated over the little flare that falls in to score two. But the reality is, it’s not the flare that kills you, it’s the two walks before the flare.”

This season, the ’Bows have been held to three or fewer runs in four Sunday games. They are 4-5 overall on Sundays, including 1-2 in Big West games on that day.

“It was disappointing,” Trapasso said. “You’ve got to be able to score on Sunday. And you want to be able to limit the (opponent’s) scoring. I thought there was a four-run swing there with the two base-running mistakes — both would have come around to score — and two runs we could have prevented that we gave up. At the end of the day, you have to be better on Sunday than that.”