Miles Mastrobuoni comes through in a pinch

Miles Mastrobuoni has been one of the most productive pinch-hitters in the league this season

The other week, Ryan Blake wrote a piece looking at the 2025 Mariners’ penchant for pinch hitting, and the results were...unsightly, to put it mildly.

The constant barrage of pinch-hitters has, unsurprisingly, not borne much fruit for the Mariners, but there were a couple exceptions in Ryan’s analysis: Mitch Garver and Miles Mastrobuoni. Mastrobuoni’s success is especially remarkable considering he is tied with Donovan Solano for the second-most pinch-hit at-bats in baseball this year (19); only Randal Grichuk of the Diamondbacks has more (25). But Mastrobuoni has been so much more successful than Solano in these situations because unlike Solano, the Mariners are selective and purposeful in the scenarios where they use him and the desired results of his at-bat.

The lefty-hitting Mastrobuoni has had the platoon advantage in 90% of his pinch-hitting appearances compared to just over 55% for Solano (and about 50% for Garver and Moore). That’s the highest mark for any player with more than 15 pinch-hit appearances. Unlike Garver and Solano, Mastrobuoni also has the benefit of speed on his side, with 81st percentile sprint speed helping him stay out of rally-killing double plays. Mastrobuoni has one of the lowest percentages of grounding into a double play; he’s only done it twice this season in 24 opportunities to do so. As Ryan noted, part of Solano’s negative value in pinch-hitting situations is that he’s had the most opportunities on the team to GIDP (37) and has done so over 20% of the time, which puts him in line with lumberers like Joey Bart and Jhonkensy Noel.

But credit also belongs to Mastrobuoni for making the most out of the situations he’s given. Despite coming in in high-leverage situations, “Mastro” makes a productive out two-thirds of the time, the second-best mark among pinch-hitters with more than 10 pinch-hit PAs (trailing Jose Iglesias), and he advances the runner about three-quarters of the time, third best among those hitters (trailing again Iglesias and former Mariner Justin Turner). He’s also a perfect 3-for-3 in getting down the sacrifice bunt.

It’s not flashy, but being a successful pinch-hitter is undeniably a skill. In a game where failing 70% of the time is considered successful, pinch-hitters face an even tougher challenge, coming in cold off the bench in a high-pressure situation. When facing a tough reliever, they often don’t have the option to wait out an at-bat or try again next time up. It’s do or die, every time.

“I think [Mastro] really thrives in those situations,” said Dan Wilson. “He has a really good concept of the strike zone. And the other thing you have to balance, as a pinch hitter, you want to be a little bit more aggressive, because that first strike you see might be the only strike you see, so you need to be aggressive, but you also have to not chase. And he’s been able to develop a nice balance in that.”

The ability has been hard-won for Mastrobuoni, who credits his current success to two years of “being pretty bad at it.”

“With Chicago, I was in that similar role and I just didn’t do well,” he said. “So when I came over here, I just found some things off Mags and Seitz [Bobby Magallenes and Kevin Seitzer] and even guys in this locker room who have been in different roles to make the game feel a little bit slower when you come in, and I’ve just been rolling with that.”

Those things are part mental, says Mastrobuoni, having a mindset of being ready to go “right off the rip” and part physical cues, “finding something that gets your body ready to go, that’s quick and that you can rely on.”

The mental side is just as demanding as the physical side. Pinch-hitting is a mental challenge that’s more on par with a reliever who has to monitor the game and think ahead, running multiple scenarios and preparing for moments that can turn the game’s trajectory in an instant. It’s a skill that Mastrobuoni has been refining since his time in Chicago, where he was able to spend time with Ben Zobrist, one of the best utility players of all time, and “pick his brain.”

“Having to lock in every single day that can be mentally challenging at times. But you know when you have to lock in, if you can feel the game and how it’s going, that helps a little bit, being able to see certain spots where different situations can happen and mentally playing those out.”

Being a pinch-hitting utility specialist isn’t what most kids dream of when they’re playing backyard baseball, but it’s a role that’s proven valuable year after year, World Series winner after World Series winner. It takes a special kind of player, as well, who is more than willing to put themselves and their stats aside and have productive at-bats, no matter what.

“I think a team-first mindset should be all the time,” said Mastrobuoni. “Trying not to focus on the result, that’s really hard in this game, because at the end of the day that’s what you’re judged on, what you get graded on. But I’m just trying to keep my mindset of having a good at-bat.”

“Move the runner over, that’s productive. Work a long at-bat, that’s productive. Make the guy throw more pitches, that’s helping the guy behind you. So just understanding that coming off the bench after sitting for seven or eight innings is tough, so just getting the barrel on the ball is a win...It’s whatever the team needs to win and if my opportunity is coming in late, there’s value in that.”

“There’s an art to it,” said Wilson. “There’s a trick to it. And ‘Stro’s done a really nice job at it.”