Going into the 2024 season, adding starting pitchers was a focus for the Boston Red Sox. In his first offseason as CBO, Craig Breslow decided to buy low on Lucas Giolito, hoping that new pitching coach Andrew Bailey would be able to turn him around. Giolito was coming off a second half of 2023 where he was worth -1.2 bWAR and had a 6.96 ERA over 12 starts.
The Sox signed Giolito to a two-year, $38.5 million contract, with year two being a player option. The deal also has a conditional option for 2026. The righty was supposed to lead a very young staff in 2024, but on March 1 he suffered an elbow injury that required Tommy John surgery, costing him the entirety of 2024.
He was supposed to be ready for the start of 2025, but a hamstring strain cost him almost all of April. The 30-year-old finally made his Red Sox debut on April 30 across the border in Toronto, and looked excellent. He threw five shutout innings of three-hit ball, before slowing down in the sixth and giving up two home runs. Red Sox Nation had hope after watching him, but following his start in Toronto, it was a shaky few outings.
In his second start, he allowed six runs in just 3 2/3 innings, bounced back with 6 2/3 of one-run ball against Kansas City, but then went backwards again allowing six runs in four innings. After his first four starts in a Red Sox uniform, he had a 7.08 ERA in 20 1/3 innings.
He had two solid performances in a row, before another blowup against the Angels where he couldn't make it out of the second inning. That's when things turned around for Giolito. After working with Andrew Bailey following the Angels start, he has been dominant.
Lucas Giolito continues to just dominate on the mound. pic.twitter.com/Gkoca9ucJI
— NESN (@NESN) July 4, 2025
How Lucas Giolito has turned into a top-of-the-rotation arm for the Red Sox
In his last five starts, he has a 0.83 ERA, striking out 31 in 32 2/3 innings, and he's averaging over six innings per start. If you increase the sample to the two games before his most recent poor start (his last eight starts), his ERA is still just 2.15 with five hits, two walks, and five Ks on average per outing.
One thing he credited Bailey with was helping him to fix his arm angle. In May, he had an average arm angle of 49.1 degrees, and in June he got it up to 51.4 degrees. He's getting more over the top now, which is good for his very straight fastball (his most dominant pitch) and his curveball.
In June, the righty saw a big improvement on those two pitches specifically. His curveball, though used just 3% of the time this season, saw a huge jump in chase rate from May to June, going from 8% to 80%, and saw a swing and miss increase from 20% to 25%. His fastball also saw a jump in swing and miss, going from 15% to 20%. He also induced a lot more pop-ups, which is good because he likes to use it at the top of the zone. With the improvement on his fastball, also came more swings and misses on his changeup, which almost doubled from 15% to 28%.
Giolito's improvement has been welcomed by Red Sox Nation. He has helped stabilize a struggling rotation. With his continued dominance, Red Sox fans no longer have to worry every five days when it's his turn in the rotation.