Barco did not allow a run in 25.2 innings at Double-A Altoona.
Bubba Chandler has become a household name as the No. 2 prospect in baseball. An electric arm who should debut with the Pittsburgh Pirates in a matter of weeks, Chandler has taken all the attention as the organization’s next star starter.
Chandler, Thomas Harrington, and Mike Burrows have stolen headlines as right-handed rotation options, but it’s a college lefty that is off to the best start.
Hunter Barco was selected by the Pirates in the second round of the 2022 MLB Draft. The Florida lefty needed Tommy John surgery after the draft and missed a large part of baseball activities for over a year.
When Barco debuted in 2023, he allowed six earned runs in 10.2 innings with Single-A Bradenton after a good start in the FCL league (one run over 7.2 innings).
The last two years have been nothing short of impactful and impressive, but he’s taken his game to a new level in 2025.
Starting in Double-A Altoona, Barco didn’t allow a run in his first six starts. You read that right. 25.2 innings without a run. Not an earned run. Not an unearned run. Barco was nearly unhittable. Barco set a new Curve record for scoreless innings.
8 K’s in 3 scoreless frames for Hunter Barco! pic.twitter.com/Y56S417cu2
— Altoona Curve (@AltoonaCurve) April 27, 2025
He allowed 11 hits, walked seven, and struck out 34, earning a 0.70 WHIP. Barco made his Triole-A debut on Friday, allowing one run on two hits and three walks over 4.1 innings. He struck out five to drive his season total to 39.
Barco’s 0.30 ERA is the lowest of any starter in Minor League Baseball. Not even Chandler can say that. He’s on his own island.
Hunter Barco’s 0.30 ERA is the lowest in all of MiLB among all full-season pitchers.
His .131 batting average against is also tied for the second-lowest among all full-season minor leaguers. pic.twitter.com/gvPBcEMlb0
— Young Bucs (@YoungBucsPIT) May 12, 2025
The Pirates have done well drafting and developing starters – Skenes, Jared Jones, Chandler, Harrington, Carmen Mlodzinski, Barco – despite struggling with hitting talent. Barco makes the only lefty of the bunch (outside of Anthony Solometo, who’s had a back-and-forth past few seasons).
He posted a 3.27 ERA and 1.06 WHIP through 66 innings between High-A Greensboro (3.34 ERA in 16 games) and Altoona (one run over four innings). His K/9 registers at 11.8, 6.1 H/9, and 1.02 WHIP.
One obstacle in Barco’s way this season is a likely innings cap on his 24-year-old arm. He hasn’t thrown more than 66 innings in a season since college. The most he threw in the SEC was 83 innings for the Gators during the 2021 season.
It’s not out of the question that Barco could debut in Pittsburgh this year, but he’s closing in on the halfway point to his innings total from 2024. On Sunday, he entered MLB Pipeline’s Top 100 prospects list (No. 93) and is the Pirates’ No. 5 prospect.
Regardless, Barco is paving the way to be the next starter to make the bigs and impact the Pirates’ Major League rotation in the very near future.