After long road to MLB, Hjerpe begins career with 4 perfect innings

September 6th, 2026

DENVER – ’s flight to Denver on Saturday evening for his potential big-league debut was fairly smooth – a fitting final leg to a more turbulent journey to the Major Leagues that culminated with four perfect innings of relief for his first big league win in his first appearance.

The Cardinals, who trailed 5-1 when Hjerpe entered in the fourth, took the series from Colorado with a 10-8 victory in the rubber match at Coors Field, pairing Hjerpe’s perfect six-strikeout performance with multi-hit games from Iván Herrera, Alec Burleson, Joshua Báez and Thomas Saggese and a go-ahead home run from Nolan Gorman in a six-run fifth inning.

“Everyone's journey is different,” Hjerpe, the Cardinals’ first-round Draft pick in 2022, said Sunday before making his debut. “Mine had a lot of bumps in the road, man. Sometimes those things are out of your control.

“I kind of came to terms, obviously, with this last surgery,” Hjerpe continued, noting the big bump in the road of 2025 Tommy John surgery. “It was the biggest one I've had so far. And once you go through something like that, you have to accept it. There's no coming back in six months, eight months, whatever it is. You got to start from the ground up and kind of hit the ground running when you can and take it day by day.”

There have been only two Major League debuts with a longer perfect performance since at least 1900: Max Kranick, who went five innings on June 27, 2021, for the Pirates; and Max Scherzer, who went 4 1/3 innings on April 29, 2008, for the D-backs. Hjerpe got through four innings on 54 pitches, 41 for strikes.​

Hjerpe, the Cardinals’ No. 18 prospect per MLB Pipeline, was called up from Triple-A Memphis on Sunday. He had arthroscopic elbow surgery in 2023 and ‘24, and he had been building back from his Tommy John surgery since being activated in the Minors on June 5.

“In my last outing, I threw [74 pitches], so we're in a pretty good spot now,” Hjerpe said. “A pretty hefty workload. I talked to [manager Oliver Marmol] today. I'll be ready in the bullpen for however many innings they need me.”

Marmol indicated he’d use Hjerpe’s preparation as a starter to complement the bullpen arms, potentially using him as early as Sunday for long relief following Kyle Leahy’s start.

“We will not use him as a reliever,” Marmol said. “He will piggyback, but he will stay on a starter's schedule.”

Hjerpe took the spot of Hancel Rincon, who made his debut Friday and pitched again Saturday, generally struggling with seven runs in 1 1/3 innings.  Rincon was optioned to Memphis.

Marmol said he likes what he has heard of Hjerpe’s potential, noting his “high ceiling. He’s got some funk. Swing and miss. Tough at-bat, left on left.”

Hjerpe posted a 0.95 ERA in August, pitching 19 innings and striking out 27.

“When you come back from surgery, command is the one thing to kind of be delayed a little bit,” Hjerpe said. “But as far as command, I think the only thing really left for me to do is have that feel as soon as I let the ball go and get that consistency and repetition in, and being able to repeat it has been the main thing. But other than that, my mechanics and all that stuff felt smooth from day one.”

The 25-year-old from Davis, Calif., has been confident this debut was coming as he pitched in the Minors this season. He was given an inkling that it might be sooner rather than later a couple of days ahead of time.

“I slept with my ringer on that night,” Hjerpe recalled with a laugh. “I turned that thing all the way up. Yeah, I was definitely waking up if I got a call.”

Once he found out Saturday, it was a whirlwind trip to join the Cards in the second city of a three-city road trip.

“I was ecstatic to be on the way to Denver,” Hjerpe said.

Hjerpe took a little time to explore the ballpark before his first workout, checking out the wooded area behind the center-field fence next to the visitors’ bullpen.

“I didn't even know there was a trail back there in that forest area,” Hjerpe marveled. “That was a pretty sick experience. This place is awesome, and I’m happy to be around this group of guys.”

Hjerpe also had about 20 friends and family out in the stands, all of whom dropped what they were doing to get to Denver for his debut. He mentioned his wife, his parents, his best man and groomsmen from his wedding, and many more.

“Patience is a virtue, man, and it's paying off today,” Hjerpe said. “I'm just happy to be here and excited to help these guys out.”

Marmol echoed Hjerpe’s enthusiasm.

“It will be exciting to see it in person and watch him make adjustments along the way,” Marmol said. “I'm pumped to have him here and take a look at it.”