The Offseason Monitor: Red Sox Acquire Sonny Gray
Boston fortifies its pitching staff by adding Gray to boost their 2026 season.
The 36-year-old agrees to forgo his no-trade clause to join the Red Sox and help them capitalize on their contention window. Gray is in the final year of his reworked extension, earning $31 million in 2026, with a mutual option for $30 million in 2027 and a $10 million buyout. Additionally, the Cardinals will send $20 million in cash to Boston along with Gray to offset part of his 2026 contract. Returning to St. Louis will be LHP Brandon Clarke and RHP Richard Fitts. Clarke is Boston’s #5-ranked prospect, and Fitts has split time between the majors and minors, making 14 total MLB starts from 2024 to 2025.
Sonny Gray’s 2026 impact
Going to Fenway Park has not been an easy task for Gray. He owns a career 0-4 record, allowing the Red Sox to hit for a .325 AVG and .895 OPS. Keep in mind this is a small sample size, through 26.1 innings pitched - but it could be alarming for potential fantasy owners.
Going through Gray’s pitcher profile, we can see he still grades out very well on fScores.
The underlying numbers are still okay.
26.7% K%
21.6% K-BB%
42.4% Groundball Rate
For Sonny to have more success in Beantown, he needs to keep the ball in the park. The .329 BABIP in 2025 is concerning, given that the St. Louis defense posted a fielding percentage above league average. Boston had the most errors committed by a team in 2025, which will not help his cause.
We can expect another consistent season from Sonny, starting 30+ games and posting decent numbers. As long as his defense behind him plays well, Sonny will have another good season.
Where do Fitts and Clarke fit in St. Louis?
Richard Fitts will almost definitely begin the season in the Cardinals’ rotation. He has only 45 big league innings under his belt, so the numbers aren’t fully balanced yet. Some good signs are that changes were made to his pitch mix toward the end of the year, which positively affected his JA ERA.
St. Louis really needs arms to add to the rotation at this point. Adding Fitts, who is 25 and has multiple years of control left, seems like a good move. Who knows what they could tap into and unlock?
Brandon Clarke is ranked Boston’s #5 prospect according to MLB Pipeline. He stands 6’4”, 220 lbs. Obviously, with a frame that size, Clarke throws 95-98, touching 100 mph on the fastball. In 2020, he underwent Tommy John surgery during his Junior high school season. Ultimately, Clarke went the college route before being drafted by the Red Sox in the 2024 draft.
The fastball grades out as his best pitch, and he dominated the Low-A affiliate. After three games started, he earned a promotion to A+ and had a rough go of it. The K% lowered from 47.2% to 31.2% and the BB% rose from 5.6% to 18%. It’s such a small sample size with 141 pitches at A and 576 at A+. Could the Cardinals pivot and try to make Clarke a premier reliever? He definitely has fantastic stuff, as shown by the fScores below.
Overall, it feels like a balanced trade. Boston gets another starter to bolster their rotation and will have to pay $21 million at the minimum for him. Compared to free-agent market options that will demand $25-30 million in AAV, Sonny’s deal is much cheaper.
St. Louis gains a couple of interesting pitching options and clears a large portion of money from their books, even with paying Boston $20 million.
Check out more prospect analysis on the two new Cardinals in this X thread from Tim!