Brett Karalius has been champing at the bit for two years to earn his first start for College of San Mateo.

When the sophomore right-hander got the call Tuesday, he delivered — big time.

Karalius joined the Bulldogs’ rotation by firing the first no-hitter for a CSM pitcher in at least a quarter century in a 10-0 win over De Anza at Bulldog Stadium.

The sophomore allowed just two base-runners and set down the last 23 batters he faced, earning his 10th strikeout of the afternoon by getting a swing-through on a fastball from pinch hitter Hansel Monleon to end it.

“It was pretty crazy,” Karalius said. “I struck the last guy out. So there was a pretty good dog pile in front of the mound.”

With CSM ranking eighth in Northern California with a 3.67 ERA, rotation spots have essentially been spoken for. The three-man rotation of Sean Prozell, Jamie Kruger and Nico Zeglin hadn’t missed a start this season. That changed Tuesday, however, when Zeglin was a late scratch, leading to Karalius being announced as the Bulldogs’ starting pitcher three hours before game time.

“I’ve wanted to (start),” said Karalius who’s had 28 career relief appearances, including 13 this year. “But all three of our starters are doing really well. So, I can’t complain.”

Karalius made as good a case as is even possible to earn another start. He allowed just one walk on the day, issuing a free pass the second batter of the game, Samio Uze. Then in the second inning, Cameron Casteneda reached on an error to lead off the inning. Casteneda was wiped out when the following batter, Austin Tremelling, grounded into a double play.

De Anza did not have a base-runner reach the rest of the day.

Karalius had not previously pitched a no-hitter at any level. He had come close, tallying several one-hitters, most recently for Pacifica Joe DiMaggio last summer.

Tuesday, both his fastball and curveball felt good coming out of his hand from the outset, he said. And it occurred to him fairly early on, in the fourth inning, he had a no-hitter in progress.

“But I was trying not to think about it too much. I didn’t want to jinx myself,” Karalius said.

By that time, Karalius had all the run support he needed. CSM freshman leadoff hitter Christian Ontai drilled his second home run of the season, a two-run shot in the third inning. The Bulldogs added three more in the fourth, highlighted by an Ontai two-run double. The freshman added a three-run double in the eighth to break the game wide open.

Ontai was 3 for 5 with two doubles and a home run, and a career-high six RBIs.

“He was locked in at the plate,” Karalius said. “He was seeing the pitcher, obviously, very well. His home run, off the bat I knew it was a home run.”

With Karalius rolling into the ninth inning, he stepped onto the mound knowing full well the gravity of the situation. And with it, he got some added adrenaline.

“Last inning I was pretty amped, honestly,” Karalius said.

He seized on a spike in velocity by striking out the first batter of the inning, Scott Fernald. Then Tyler Jochen followed by giving Karalius a scare by shooting a line drive to the outfield, but it sailed right into the glove of Ontai in left for the second out.

When Monleon came to the plate as a pinch hitter, Karalius was confident in challenging the strike zone knowing the freshman had yet to face him. Monleon took a first-pitch fastball for a strike then was late in fouling off another fastball. So, when CSM catcher Danny Carnazzo put down the sign for the fastball again, Karalius was confident to rare back and shoot for his best bolt.

“The fastball was called so I was just like, ‘I’m going to put a little extra on this one,’” Karalius said. “And I got it by him and that was the game.”

Karalius, a 2017 graduate of Terra Nova, is one of many former Tigers who are pitching collegiately.

Three former Tigers — Dylan McDonald, Nate Rumb and Tony Zamagni — have logged starts for Skyline College this season, combining for a 10-5 record. Skyline transfer Ray Falk is a redshirt junior at Ole Miss, and CSM transfer Jared Milch is also pitching in the Division I ranks as a true junior at Stony Brook in New York.

With the win, second-place CSM (9-4 Coast Golden Gate, 20-11 overall) gains ground in the Coast Conference Golden Gate, moving to within one game of first-place Mission. The two teams square off in a two-game series to close the regular season starting Tuesday, April 23.