Cards' No. 20 prospect Mautz makes anticipated MLB debut out of 'pen

MILWAUKEE -- Brycen Mautz’s MLB debut was anything but ordinary.

It’s agonizing enough waiting for your first big league moment. But for Mautz, he had to wait longer than most -- and travel hundreds of miles across the Midwest.

St. Louis’ No. 20 prospect, per MLB Pipeline, was the scheduled starter for Sunday’s series finale in Cincinnati before it was postponed due to rain. That meant Mautz, and his entire family of 10 who made the trip to Ohio, had to pack up and head to Wisconsin, all eager for the opportunity to arrive.

That special occasion finally came in the sixth inning of the Cardinals’ 5-1 loss to the Brewers on Monday afternoon at American Family Field.

“It was definitely a little bit of a rollercoaster, getting ready for that one,” Mautz said. “You mentally prepare to face that [Reds] lineup, then come here, like, ‘OK, now I have to remember what it’s like to come out of the ‘pen and be ready for that situation.’ But it’s what the game requires.”

Mautz’s final line of three innings, two runs, two walks and a pair of strikeouts won’t raise eyebrows, but what he did during those frames displayed why the Cardinals are high on their left-hander.

Mautz immediately found himself in trouble after allowing a single and a walk to the first two batters he faced. He recorded his first out on a fly ball to the warning track before Garrett Mitchell tagged him for an RBI single, which Mautz made worse after a wild pitch -- his second of the inning -- put two runners in scoring position.

That’s where his debut could have gone awry. The Cardinals started moving in the ‘pen, with the Brewers on the verge of a big inning and the 24-year-old struggling to command his pitches. Instead, Mautz got Joey Ortiz to chase a slider in the dirt for his first MLB strikeout before following that up with a perfect 2-2 slider that Jackson Chourio swung over to escape the jam.

“Coming into this, I’d been told a lot, ‘Be yourself, you don’t have to do more,’” Mautz said. “It’s tough, in the moment with that. That was the main thing for me, trying to do too much with the fastball and all the breaking balls that were down and sprayed. … [Let] that get to me a little bit, [but] found a little bit of rhythm going out there for the last one, able to feel my legs again, get under me. Now that my stuff will play, I just got to make the pitches.”

Mautz came back out for the seventh and once again limited the damage to one run after the Brewers had runners on second and third with one out. This time, the rookie got help from his defense when right fielder Jordan Walker threw a 92.4 mph laser homer to nab Christian Yelich attempting to score from third.

That’s when Mautz settled in, returning for the eighth and needing just nine pitches to set down the first-place Brewers in order.

“Didn’t get ahead to fill [up the zone] as much as he would have liked, but for his first time out, I felt like with all the emotions and everything that goes with a debut, he showed well,” manager Oliver Marmol said. “He was able to make some pitches there for the punchouts. That was good to see that he didn’t get sped up and he was able to stay in the moment there.”

Mautz’s outing was able to save the bullpen as well, which is now extra rested after Sunday’s postponement following a doubleheader on Saturday. That’s important for this Cardinals club, with their next five games (Brewers, Cubs) against division opponents in a tight NL Central.

The organization’s 2025 Minor League pitcher of the year’s role for the rest of the season may depend on the health of the big league’s pitching staff, but getting Mautz, who had a 2.90 ERA in nine starts with Triple-A Memphis before his callup, experience could pay off in the future.

“It’s the highest level of the game, but it’s still the same game,” Mautz said. “It’s super cool. I’m really grateful they gave me this chance, because they easily could have sent me back [to the Minor Leagues], so that means a lot to me.”