How fatherhood has helped Mattson thrive with Pirates

This story was excerpted from Alex Stumpf’s Pirates Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

CHICAGO -- Written on the side of Isaac Mattson's glove in mint-blue lettering is the name “Theodore Oakley.” It’s a name that he quite literally holds close to his heart as he sets up for every pitch, and someone he credits his success to in his breakout season. Coming into the year, Mattson had pitched just seven Major League games. Now, he’s emerged as one of the Pirates’ top leverage arms.

When pitching coach Oscar Marin and manager Don Kelly reflect on when they thought Mattson could emerge as a legitimate bullpen arm, they both go to his appearance this Spring Training against the Yankees in Tampa. Mattson had been sitting around 91 mph in camp to that point, but in that March 16 game, he was hitting 94-95 mph. He’s held that velocity this season, and with his arm angle, Marin describes his fastball as “invisible” at that speed.

That game in Tampa was Mattson’s first game back after meeting Theodore, or “Teddy.” He and his wife, Devin, welcomed him into the world on Feb. 26, and their first child also brought the changes Mattson needed to become the best version of himself on the mound.

“Definitely some dad strength, definitely some perspective shift,” Mattson said, a parent himself now after using his platform with the Pirates the last two years to tell the story of his mom.

Mattson’s baseball journey has been one of resilience. After debuting with the Orioles in 2021, he found himself out of affiliated ball and pitching for the local Washington Wild Things of the Frontier League in 2022. When he signed a Minor League deal with the Twins in 2023, his first game back in Double-A was defined by him walking the bases loaded and allowing a game-losing grand slam.

Games like that had him wondering what he was doing. He was better than a lot of these players, or at the very least, he should be better. He and Devin talked and prayed, wondering if the Major League dream was still worth pursuing.

Mattson, an Erie native and Pitt graduate, signed a Minor League deal with the Pirates in 2024 and excelled. The highlight of the campaign was a trip to Rochester, N.Y. for a Kenny Chesney concert, where Devin gave Isaac a friendship bracelet that said “Dada.”

Becoming a father was a catalyst for Mattson. He can’t just have those games where he left thinking he should have been better. He needed to be better.

“Down in Florida, just sitting at my Airbnb after practice each day, just giving my wife and Teddy calls throughout the afternoon and work day, the perspective shifted,” Mattson said. “This is what I’m deciding to do, taking away that time from people that I want to be around and spend this time with.

“If I’m not able to do that, then I really want to give it all I got. Do it for them. Do it for what’s important, which is family.”

Mattson has seven siblings and now 20 nieces and nephews. Growing up, he and his family would do child care for Sunday School every other week. Fatherhood always seemed like a calling, following the example his parents, Edward and Debra, set.

Parenthood has been a theme of Mattson’s career even before Teddy. His mother, Debra, took her life in July of 2021, and he has used his platform to raise awareness on mental health. The Mattson family also organized a walk to raise money for scholarships in her name.

Mattson learned a lot about being a parent from Debra, especially on unconditional love. He remembers the support that she gave each kid, taking them to practices or events and showing that she cared and would be there.

“I’m trying to take that into my own experience as a parent now,” Mattson said. “Try to encourage, even though he doesn’t know what’s going on. Just try to be that positive person. ... I’m trying to honor her as a parent myself.”

Mattson is trying to be that supportive, loving figure in his son’s life now, even if he’s just now only starting to recognize his name. He doesn’t know what baseball is yet or what dad does, but he’ll be in attendance.

“It’s always nice to have him in the stands, even if he won’t remember,” Mattson said. “My wife and I will.”