Five Boston Red Sox Pitching Prospects Who Broke Out in 2026

For the better part of the last 20 years, the Boston Red Sox have struggled to consistently develop homegrown starting pitchers. However, under Chief Baseball Officer Craig Breslow, the team has placed greater emphasis on pitching development. As a result, the team has become somewhat of a pitching factory, developing Payton Tolle, Connelly Early, Anthony Eyanson, and Jake Bennett, to name a few. 

After trading Eyanson and 2025 first-round pick Kyson Witherspoon to the Baltimore Orioles for All-Star catcher Adley Rutschman, the Red Sox now rank in the bottom 10 in farm system rankings. 

As Breslow looks to rebuild his depleted pitching pipeline, these five pitchers have put their names on the map with breakout 2026 seasons. 

The following rankings are from SoxProspects.com.

The 2026 Red Sox Minor League Pitcher of the Year recipient, Brown was selected in the eighth round of the 2025 MLB Draft out of Old Dominion University. The 6-foot-5 left-hander made his professional debut in 2026 with the Single-A Salem RidgeYaks. In five starts with Salem, Brown allowed 11 runs (six earned) on 15 hits, striking out 32 and walking 13 in 23.1 innings before being promoted to High-A Greenville on May 5.

In 17 appearances with the Drive, Brown posted a 3.78 ERA with opponents hitting .250 off him. While the surface numbers don’t jump off the page, the 22-year-old posted incredible strikeout numbers while limiting walks. His 32 percent strikeout rate ranked in the 85th percentile among High-A pitchers, while his 6.9 percent walk rate fell in the 86th percentile. Brown was especially good at getting hitters to chase pitches out of the zone, with a 38.2 percent chase rate that ranked in the 97th percentile. 

After entering the season as the No. 60 prospect in the system, Brown has jumped to the No. 20 prospect in the organization, according to SoxProspects.com.

A member of the 2025 Red Sox international amateur free agent class, the 18-year-old right-hander got the highest signing bonus of any pitcher in the IFA class. After spending the 2025 season in the Dominican Summer League, Delzine began his stateside career in the Florida Complex League in 2026.

In 11 appearances (seven starts) in the FCL, Delzine posted a 2.72 ERA over 39.2 innings, striking out 9.76 batters per nine innings and walking 4.08. After a strong FCL showing, the team promoted Delzine to Salem on July 21, where he became the youngest player at the level. In seven starts with the RidgeYaks, the right-hander allowed just seven earned runs on 21 hits over 21 innings. During his time with Salem, Delzine's strikeout rate ticked up from 26.4 percent in the FCL to 34.6 percent. He also cut his walk rate nearly in half from 11 percent to 5.8 percent. 

As a result of his strong season, Delzine rose from No. 23 in SoxProspects' rankings to the No. 6 prospect in the organization and the second-ranked pitcher. 

A 2024 fourth-round pick of the New York Yankees, the 23-year-old right-hander was acquired by the Red Sox in an offseason deal with the Chicago White Sox in exchange for reliever Jordan Hicks and pitching prospect David Sandlin. 

Ziehl began the 2026 season in Double-A Portland, posting a 4.33 ERA over 17 starts, with opponents hitting .278 against him. The team promoted Ziehl to Triple-A Worcester on Aug. 4. In eight starts with Worcester, Ziehl posted a 4.17 ERA. 

Like Brown, Ziehl's surface stats don't jump off the page. However, he paired his already strong control (4.8 percent walk rate in 2026) with much better strikeout numbers after working within the Red Sox pitching infrastructure. After striking out only 19.8 percent of batters faced in 2025, the 23-year-old raised his strikeout rate to 24.7 percent in 2026. 

Ziehl is ranked the No. 21 prospect in the Red Sox system, a seven-spot rise from where he started the season. 

The 20-year-old right-hander had his 2026 season cut short after just three starts when he tore the UCL in his right elbow, requiring Tommy John surgery. While his season ended early, Valera looked like a major riser in both the Red Sox system and league-wide prospect rankings, entering Baseball America's Top 100 before the injury. In 9.1 innings, Valera allowed only two earned runs on four hits, striking out 47.2 percent of batters he faced and posting a 53.2 percent whiff rate. 

Despite missing the final three months of the season, Valera hasn't seen much of a drop in his stock and enters the offseason as the top-rated pitching prospect in the Red Sox system and No. 4 overall. 

Whenever Valera returns to full strength, he will undoubtedly be the top name to watch in the Red Sox system.