This is certainly a guy Chicago Cubs fans should take notice of, as right-handed pitching prospect Mason McGwire has been promoted to South Bend. The right-handed starter has come out of nowhere in 2026 and has quickly established himself as one of the organization’s new star pitching prospects.
The son of MLB slugger Mark McGwire, Mason is making a name for himself in the Cubs’ minor league system. It took some time for the pitcher to get going after he was drafted in 2022, but the stuff looks legit, and now the Cubs want to see him at the next level in High-A Ball.
The 22-year-old has pitched in 10 games down in Myrtle Beach so far this season, including five starts. It may only be a 30-inning sample size, but McGwire is racking up the strikeouts, so a new challenge will be thrown his way.
It’ll be interesting to see how aggressive the Cubs will be with McGwire this season. At 22-years-old, he’s a bit behind at High-A Ball, but if he truly has figured it out and has everything clicking, then it wouldn’t be surprising if he’s at the doorstep of the majors by the end of this season.
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Taken in the eighth round of the 2022 MLB Draft, McGwire is eligible for the Rule 5 Draft after the end of this year. So, if the Cubs want to protect him from getting plucked away from another team, he’ll have to get added to the 40-man roster once the 2026-27 offseason kicks off.
McGwire may get fast-tracked through multiple levels in the minor leagues this year, so the team can see just how much he has developed and if there’s a chance he could become a potential piece as soon as next year.
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A handful of great outings will catch your eye, and although the sample size remains relatively small, there’s no denying that Mason McGwire is in the midst of a major breakout season in the Chicago Cubs farm system. The 22-year-old is Rule 5 eligible in December, and although McGwire is still in Low-A Ball, he’s making a strong case to get added to the Cubs’ 40-man roster with his impressive start to the 2026 season.
On Wednesday, McGwire struck out eight batters in 4.1 innings, while allowing one earned run on three hits. The right-handed pitcher did not walk a hitter and now has a 37/8 strikeout to walk ratio on the season.
Overall, in 24.1 innings pitched through eight games, McGwire has a 1.85 ERA with a 38% strikeout rate, which leads the Myrtle Beach Pelicans’ pitching staff.
You have to imagine that McGwire will be promoted to the South Bend Cubs sooner rather than later based on his dominant performance with Myrtle Beach. Looking ahead, if he continues to progress throughout the summer, then McGwire may end the year with the Knoxville Smokies at Double-A. That would be a huge development for McGwire, who was struggling just last year to gain any positive momentum.
