The Boston Red Sox have called up Kyle Harrison, the left-handed pitcher acquired in June's blockbuster trade that sent Rafael Devers to the San Francisco Giants. 

The 24-year-old Harrison pitched in the big leagues last season and briefly in 2025, but the southpaw had been with Triple-A Worcester since he joined the organization. He was called up on Wednesday and will join the Red Sox in Sacramento for the final game of a three-game series against the Athletics.

While Harrison made 12 starts for the WooSox and went 4-2 with a 3.75 ERA and 50 strikeouts over 50.1 innings pitched in those outings, he's set to assume a bullpen role for Boston. He could see action as soon as Wednesday, with rookie Payton Tolle set to make his third career start for Boston. 

Tolle, 22, will make his third career start in the big leagues Wednesday, but he'll do so on less than five days rest for the first time in his professional career. Harrison could be the long man out of the bullpen for Boston if Tolle makes an early exit against the A's.

Who is Kyle Harrison?

Harrison was a third-round pick by the Giants in 2020 and was San Francisco's top prospect heading into the 2024 season. Last year was his first season as a fulltime stater, and he went 7-7 with a 4.56 ERA over 24 starts for the Giants. He appeared in eight games for the Giants to start the 2025 season -- four starts, four relief appearances -- and put up a 4.56 ERA over 23.2 innings.

He was actually set to start for San Francisco the night he was traded for Devers, but was a late scratch when the two teams agreed to the deal. Overall, Harrison has 35 big league starts to his name with a 9-9 record and a 4.48 ERA over his 39 appearances in the Majors.

Harrison will give the Red Sox another young left hander to use down the stretch, along with Tolle and Connelly Early, who struck out 11 A's in his Major League debut Tuesday night.