Talk Sox Red Sox Minor League Starting Pitcher of the Month - March/April 2025

The first month of the Minor League Baseball season is in the books, so it's time to break down some of the top performers in Boston's system thus far. Full season ball kicked off during the last weekend of March with Triple-A Worcester, while Double-A Portland, High-A Greenville, and Low-A Salem got started the following week. With that being said, farm teams are about to the point of the season where sample sizes are starting to mean more and campaigns are beginning to take shape. 

The Red Sox have developed a pretty solid group of pitchers in the minor league ranks over the past couple of seasons, which has been highlighted by impressive performances from multiple arms across each level. Names such as Brandon Clarke, Jojo Ingrassia, and Connelly Early have received a lot of attention, but among the best arms in the system, it's the 24-year-old Auburn product that has emerged as the best pitcher in the month of April for the Red Sox minor leagues.

Hayden Mullins was a 12th-round pick (369th overall) in the 2022 draft out of the University of Auburn. It was a tough conclusion to his college career, as his junior season was shortened due to Tommy John surgery that would keep him off the mound until August 2023. It was then that Mullins would finally make his professional debut, though it was just a brief four-game stint for the lefty between the Florida Complex League and Salem.

2024 was Mullins' first full season in the minors, which was quite the encouraging sign considering he entered Boston's system having only thrown 53 1/3 innings during his college career at Auburn. In 2024, Mullins managed to throw 89 innings across 22 games and 17 starts for Greenville. Mullins was a staple for the Drive's pitching staff, as he posted a 3.94 ERA while striking out 30.3% of the batters he faced. 

Fast forward to 2025 and Mullins has earned himself a promotion to Double-A following a dominant month of April in Greenville. He has appeared in four games, three of which he started, and all of which he threw at least four innings. In his 17 total innings of work, Mullins has given up just two earned runs while striking out 27 against just three walks. His 27 strikeouts thus far rank third among all Red Sox minor leaguers, while his 1.06 ERA ranks second (minimum ten innings pitched). He has done a great job at limiting baserunners, as he's sporting the best WHIP in the system at 0.82, as well as an impressive .186 opponent batting average. 

All four of his appearances to this point have been great, but it's his most recent start, which happened to be his final start for Greenville, that was his best. He fired off four shutout innings while allowing just one baserunner via a hit and struck out six, leading Greenville to a victory over the Hub City Spartanburgers (TEX).

Because of the injury history and overall profile, it seems as if Mullins is projected to end up in the bullpen down the road, but he has certainly established himself as an effective starter for the time being. It's a distinct four-pitch mix for Mullins, with the fastball and slider really being his two main offerings. His fastball sits in the low-90s but has topped out at 95 mph, and plays up due to his low release point and extension. The slider sits in the low-80s with a tight shape and also plays up due to Mullins's ability to locate it well. He also features a curveball and a changeup, which are both a work in progress and will likely be the determining factor for how long he lasts as a starter. 

After a solid campaign in his first full season of pro ball a year ago, and now with a hot start to 2025, Hayden Mullins has become a name to keep an eye on moving forward. Whether it's as a middle to back-end of the rotation starter or as an impact reliever, this is certainly an arm that could find his way to Fenway given his current trajectory. 

Interested in learning more about the Boston Red Sox's top prospects? Check out our comprehensive top prospects list that includes up-to-date stats, articles and videos about every prospect, scouting reports, and more!