The Arizona Diamondbacks face a challenging offseason in which they must make major additions to the pitching staff in order to compete in 2026.
With the departures of Zac Gallen and Merrill Kelly to free agency, and the injury to Corbin Burnes, the team is left needing to add two major league arms to the starting rotation, and need to bolster the bullpen as well.
There is some hope that Burnes may return sometime around the All-Star break, as he stated that was his goal in an interview just after the season had concluded.
Related Content: Arizona Diamondbacks’ Corbin Burnes Aiming for July Return
More recently, General Manager Mike Hazen spoke about the potential boost the club might get from Burnes return mid season. Alex D’Agostino wrote recently:
“Hazen said he views the returning arms coming back as more of a boost to the D-backs’ roster, rather than them being the solution to a need to be filled in at a later date.
“We will be welcoming them back as we move through the season. It will be a boon to what we’re trying to do. So how do we get to that point is what I’m focused on right now,” Hazen said.
What Can Diamondbacks Expect From Corbin Burnes When he Returns?
Arizona Diamondbacks Corbin Burnes (39) pitches against the Pittsburgh Pirates at Chase Field in Phoenix, on May 27, 2025. | Joe Rondone/The Republic / USA TODAY NETWORK via Imagn Images
Looking back over the last five years, the track record of top rate pitchers who returned mid-season from Tommy John Surgery is a mixed bag. For the most part, it takes well beyond the first half-season back for even elite pitchers to fully regain their form.
For the purpose of this article, we are only looking at Cy Young contenders and All-Star level pitchers. They would be expected to make stronger contributions after returning. The focus is on contributions during the return year.
Moderately Successful Returns
Tommy John Mid Season Returnees | Jack Sommers
Note: aWAR used in these tables is the average of Baseball Reference and Fangraphs WAR
Chris Sale posted an excellent 3.16 ERA returning 13 months after surgery, a similar timeline to what Burnes has targeted. But note he averaged less than five innings per start. Sale missed almost all of 2022 with unrelated injuries, and eventually bounced back to win a Cy Young in 2024.
Hyun-Jin Ryu came back to post 11 starts less than 14 months after surgery, also averaging less than five innings per start. While he posted a decent ERA, the peripherals did not match. He returned to South Korea to pitch in the KBO in 2024.
Shane Bieber had a successful return for the Blue Jays, going on to throw 18.2 Postseason innings. He was mostly effective.
Poor Regular Season Returns
Poor Results immediately following return from surgery | Jack Sommers
Walker Buehler struggled mightily in the rotation after returning and into the NLDS, where he was hammered. But he managed to post two good starts in the NLCS and World Series and was on the mound in relief when the Dodgers took home the 2024 title. He struggled again in 2025.
Robbie Ray posted a high ERA in seven starts, and averaged just over four innings per start. He went down with a hamstring injury in late August, ending his season. He did bounce back in 2025 to post a solid season, however.
Incomplete Returns
Incomplete Returns | Jack Sommers
The above table is comprised of pitchers who returned in season, but most of them late in the year. These are Carlos Rodon, Luis Severino, Noah Syndergaard, Tyler Glasnow, Garrett Crochet, and Jacob deGrom.
All of them went on to have success in subsequent seasons, but that first year back saw very limited innings total.
Due to either scheduled return timetables, or setbacks during rehab, four of the six players in this table did not come back until September of the following year. That despite all but one of them undergoing surgery anywhere between February and June of the previous year.
Summary
Every athlete is different, and every arm, surgery, and situation is unique to that player.
The purpose of this breakdown was to illustrate the wide range of outcomes. The Diamondbacks are rightfully considering anything they get from Corbin Burnes in 2026 as a boon or a bonus.
They are not counting on him being an ace-level stalwart even in late 2026. Neither should you.
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