How Mason Montgomery Became The Pirates Bullpen Weapon Nobody Saw Coming

After a season of transformation, Mason Montgomery has risen from an overlooked acquisition to a formidable force in the Bucs' bullpen, redefining what it means to be a star closer.

Mason Montgomery didn’t try to chase the streak, and in the end, that may have been the whole point.

From July 27 to Sept. 24, the Pirates left-hander worked 25 straight scoreless outings, the longest run by a Pittsburgh pitcher since 1900. It finally cracked on the penultimate day of the regular season, when a walk-off home run brought the run to an end. Montgomery came right back and saved the season finale.

What followed over the last stretch of 2026 turned him into one of the most dominant bullpen arms in baseball. From the Trade Deadline on Aug. 3 through the end of the regular season, Montgomery logged a 1.14 ERA with a 40.9% strikeout rate and 16 saves.

All three marks landed in the top five among MLB relievers with at least 20 innings pitched in that span. His 16 saves also topped Cincinnati’s Emilio Pagán (14), Milwaukee’s Trevor Megill (12) and St.

Louis’ Riley O’Brien (12) over the final seven weeks.

That kind of finish looked a lot different from where Montgomery started.

He came up through the Rays’ system as a starter, and for much of his young career, that’s still how he saw himself. The shift to relief in 2024 changed everything.

In his third full professional season, he found success out of the bullpen, made his big-league debut and called it a “shock.” Then came another surprise in 2025 when he made the Opening Day roster, something he described as “unexpected.”

The move to relief also unlocked more velocity. Montgomery said he picked up three miles per hour once he shifted to the bullpen, and even though the routine took some getting used to, the results were immediate: more strikeouts, more consistency, more life on the fastball.

Then came another twist - a trade to the Pirates in a three-team deal before the 2026 season. At first, Montgomery could have been viewed as part of the larger Brandon Lowe deal, but Pittsburgh saw a left-hander who could run his fastball past 100 mph and had room to grow into something much bigger.

The Pirates eased him into different roles. With Gregory Soto handling most of the high-leverage work against lefties in the first half, Montgomery opened five games, worked the middle innings eight times and gradually moved toward the back end of games. That transition got another boost in mid-June, when pitching coach Bill Murphy introduced a two-seam fastball that made him even tougher to square up.

Soon enough, Pittsburgh started handing him the ninth inning. Montgomery got his first save on July 11 against Milwaukee, then opened in Cleveland a week later. By the time the season closed, he had piled up 18 saves over the final 68 games.

Still, nobody in the organization is rushing to pin a permanent label on him.

“I see myself as a left-handed reliever,” Montgomery said. “They have control over when I throw, so I do think it's fun closing games.

I enjoy it. I take some pride in it.

I'm glad I've been able to work and get to this point. But at the end of the day, if they want me to throw in the fifth inning or the first inning, yeah, I'm gonna throw.”

Murphy is just as comfortable keeping the definition loose.

“I don't think of it as closing,” Murphy added. “Yes, he's pitched in the ninth inning a ton, and I think in today's game, if there's a spot in the eighth inning where he's going to face the best hitters, maybe he pitches in the eighth inning. But what I do feel pretty confident saying is he is one of the best relievers in baseball."

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