MILWAUKEE (AP) — From college walk-on to major league starter, Chicago Cubs right-hander Alec Mills had to earn most every break he got.

On the brink of big league history, he was happy to welcome this bit of luck: expecting to see two-time batting champion Christian Yelich in the on-deck circle, Mills looked over and saw his backup instead.

“That kind of surprised me,” he said.

This one surprised just about everyone.

Mills cruised through baseball’s second no-hitter this season in just the 15th start of his career, completing the gem in a 12-0 romp over the Milwaukee Brewers on Sunday.

Mills got Jace Peterson — who replaced Yelich, the 2018 NL MVP, on defense late in the blowout — to hit a routine grounder to shortstop Javier Baez with two outs in the ninth. Baez completed the play, and the Cubs swarmed around Mills, tearing off his cap and pulling at the smiling right-hander’s uniform after his first career complete game.

“It just hasn’t really hit me yet,” the 28-year-old said. “It’s kind of crazy, I didn’t even know how to celebrate. Just something that all came together today. Obviously a memory I’ll have forever.”

Mills (5-3) threw 114 pitches and hardly had any close calls in Chicago’s 16th no-hitter.

Mills struck out five and walked three. His five strikeouts are the fewest in a Cubs no-hitter since Ken Holtzman in 1969. He only induced five swings and misses, tied with Oakland’s Dallas Braden during his perfect game in 2010 for fewest in a no-hitter since at least 1988, per Stats Inc.

“I can promise you it was not a slow heartbeat,” Mills said. “I had to kind of take a seat and calm myself down. It was tough. I had to take a lot of deep breaths and get into a good mindset.”

Chicago White Sox ace Lucas Giolito threw baseball’s other no-hitter this season against the Pittsburgh Pirates on Aug. 15.

Milwaukee had not been held hitless since Detroit’s Justin Verlander pitched the first of his three no-hitters on June 12, 2007. It’s the fourth time the Brewers have been no-hit.

Held without a hit through three innings, the Cubs broke through against Milwaukee in the fourth against starter Adrian Houser (1-5) due in large part to shoddy fielding by the Brewers. Kyle Schwarber drew a one-out walk, Baez reached on an error and Jason Heyward followed with a bloop double to left to drive in a run.

With the infield in, Jason Kipnis hit a ball directly to Brewers second baseman Keston Hiura, who had it slip out of his hand as he tried to rush a throw to the plate, allowing a run to score.

Victor Caratini followed with a run-scoring bloop single and Ian Happ connected for a two-run single as the Cubs scored five runs in the inning, all unearned.

“Nothing went right today. We didn’t play a good game,” Counsell said. “We played a poor game and we lost. We have to turn the page and know that there’s still a lot of important baseball left in front of us.”