Merrill Kelly Eyes Return After Back Injury, Aims for 2026 Season with Diamondbacks

The Arizona Diamondbacks are determined to rebound in 2026 after consecutive seasons outside the playoffs. Central to those plans was Merrill Kelly, who had been expected to anchor the starting rotation on Opening Day. However, a recent back injury has delayed his first start, prompting questions about when he might return to the mound.

Kelly recently received a cortisone and lidocaine injection to manage inflammation and pain. Following the treatment, he was able to throw a light session of catch without issue, signaling a cautiously optimistic outlook for the season. “He played catch today without problem and is optimistic about being able to pitch at backend of rotation to start the season,” MLB.com’s Steve Gilbert reported.

The Diamondbacks rotation also includes veteran Zac Gallen, giving Arizona some stability as they seek to return to postseason contention. After reaching the World Series in 2023, the team has struggled to replicate that success, finishing 80-82 in 2025.

Kelly’s situation is closely monitored, as the team hopes to avoid placing him on the injured list. His health will be pivotal in determining whether Arizona can compete effectively in 2026 and restore its position among National League contenders.

1. Injury and Recovery

Kelly’s back injury comes as a setback to both his personal plans and Arizona’s rotation strategy. The pitcher underwent a cortisone and lidocaine injection last week to reduce pain and inflammation, a common procedure for players recovering from minor back strains. Following treatment, Kelly participated in light throwing exercises and reported no discomfort. This progress is a positive sign, though the Diamondbacks remain cautious to ensure he does not risk aggravating the injury. Kelly hopes to slot into the back end of the rotation once he is fully ready. Avoiding the injured list is a priority for both Kelly and the Diamondbacks. Doing so would allow him to contribute immediately and maintain depth in the pitching staff without forcing the team to shuffle assignments or rely heavily on less experienced starters. The timing of his return will depend on continued rehab and monitoring, with Arizona likely taking a conservative approach to protect the veteran’s long-term health while maximizing his effectiveness during the season.

2. Kelly’s Role in the Diamondbacks Rotation

Kelly’s presence in the rotation is crucial for Arizona’s aspirations in 2026. Alongside Zac Gallen, he brings experience, durability, and postseason knowledge to a staff looking to improve upon recent results. The 2025 season saw Kelly split time between Arizona and the Texas Rangers, finishing with a 3.52 ERA and 12 wins overall. His consistent performance demonstrated that he remains a reliable arm capable of stabilizing the rotation and mentoring younger pitchers on the staff. Reacquiring Kelly as a free agent this offseason was a significant move for the Diamondbacks. Not only does it bolster their starting pitching depth, but it also reunites the team with a local player who has expressed a desire to conclude his career in Arizona. As the season unfolds, Kelly’s health and performance will be a barometer for Arizona’s success. His ability to pitch effectively without setbacks will directly impact the team’s chances of returning to playoff contention.

3. Background and Career Highlights

Kelly, a former Arizona State University standout, began his MLB career with the Diamondbacks from 2019-2025 before a midseason trade to the Rangers. His return to Arizona this offseason fulfilled a long-stated goal of finishing his career with the team in his home state. Over his nine-year career, Kelly has demonstrated consistency and durability, with a strong track record of innings pitched and run prevention. He remains one of the most reliable starters in the National League when healthy. His experience with both Arizona and Texas in 2025 showed his ability to adapt to new teams and maintain performance across different environments. This versatility adds value as the Diamondbacks look to navigate a competitive 2026 schedule. The combination of local roots, prior success with the team, and veteran presence makes Kelly not only a key pitcher but also a clubhouse leader. His leadership and familiarity with the organization could be as impactful as his contributions on the mound.