This Rockies Minor Leaguer K'd Arenado at 100 mph

March 16th, 2023

GLENDALE, Ariz. -- There aren’t many people in the world who can say they struck out Nolan Arenado on three pitches -- especially with the world watching.

The right-hander, who stands 6 feet, 7 inches tall, raised eyebrows with his triple-digit fastball when his Great Britain team played Team USA last Saturday at Chase Field in the first round of the World Baseball Classic.

As soon as he blew strike three past Arenado, one of the game’s elite hitters and a 2022 National League MVP finalist, the baseball world started Googling “Michael Petersen baseball” to find out who this guy was.

After all, how often do you see a 28-year-old you’ve never heard of pumping 100 mph?

One man who knew well what Petersen could do is Rockies director of player development Chris Forbes. In more than a quarter-century of scouting and talent evaluation, Forbes has never seen anyone quite like him.

Neither has most anyone else.

“I woke up [the morning after Petersen’s WBC inning against Team USA] to like 18 texts from friends in the game,” Forbes said. “They’re like, ‘What the heck?!’”

So, what’s the story here? How is it that the vast majority of us had never heard of this guy until last weekend?

Petersen, then armed with a two-seam fastball that touched 97-98 mph, along with a curveball and a changeup, was pitching for High-A Carolina in the Brewers’ organization in 2019. His control was somewhat erratic, but when the Rockies saw him unprotected in that year’s Rule 5 Draft, they jumped at the opportunity to claim him.

With a new team and new scenery, Petersen, who had a 3.00 ERA over 41 relief appearances for Carolina (54 innings) -- but also walked 5.7 batters per nine innings -- felt he was embarking on a fresh start in his quest to reach the Major Leagues.

Then the COVID-19 pandemic happened, wiping out the entire 2020 Minor League season. The next year, Petersen was told he’d need to undergo Tommy John surgery to repair the ulnar collateral ligament in his pitching elbow.

All told, when Petersen took the mound last Saturday, it was his first real game action in more than three years, outside of one Rookie League appearance on Aug. 20, 2022.

“There were some days where I was losing my mind,” Petersen said. “There were days where my shoulder started to bug me and I had to be shut down for a while. I’m seeing new guys who just got signed and they’re asking me how long ago I signed, and I’m saying, ‘2015.’ And they’re saying, ‘Oh, wow. I started high school in 2015.’”

What Petersen’s adversity created, however, was a drive to not let all that time go for naught. He began working harder in the gym, which included workouts he found tedious in the past because he had what his college roommates would call “roll-out-of-bed velocity.” He also added a four-seamer to his arsenal.

The result was 3-4 mph of added velocity and, if Petersen can harness his command, a real chance to reach the big leagues.

“After surgery, our training staff hit me with a lot of stuff I needed to do,” he said. “Pre-throwing, post-throwing, a lot of Plyo Balls, a lot of shoulder work. They were like, ‘Hey, this stuff is going to be massive for you because those tiny little muscles you’ve kind of been ignoring, they need to get strengthened or you’re going to keep getting hurt.’ So I said, ‘OK, add this to my lift day.’”

Petersen doesn’t know which level of the Rockies’ farm system he’ll be assigned to. But given that he’s already shown the determination to endure three years without pitching in a game that counted in order to keep his dream alive, can you really rule anything out for his future?

“Just to get him in a Rockies uniform and out on the mound is exciting,” Forbes said. “We re-signed him twice while he was rehabbing. If everything lines up and he’s holding the strike zone and at least getting to the areas he needs to -- he’s never going to be a pinpoint command guy -- he looks like a leverage innings guy, somewhere in the back of the bullpen.”

Petersen has been through a lot in his baseball journey to this point. But he’s here thanks to his conviction that there was only one course of action as he was dealt setback after setback beginning in 2019.

And those guys who eclipsed him in the farm ranks, the ones who were still in junior high when Petersen was drafted by Milwaukee back in 2015? He’s planning on seeing them again soon.

“I just kept thinking, ‘Once I get back on that mound, hopefully this will all be worth it,’” he said. “If you come back exactly as you were before, then yeah, it’s lost time.

“But if you come back better, that time isn’t lost.”