Diamondbacks could get best of both worlds with Merrill Kelly

The Arizona Diamondbacks traded pitcher Merrill Kelly at the 2025 trade deadline for a trio of prospects. That trade may look even better in the near future.

According to John Gambadoro of Arizona Sports 98.7 FM, there is mutual interest in a reunion between Kelly and the Diamondbacks. He also reported that fellow free-agent pitcher Zac Gallen is much less likely to return.

Kelly had stalled out at Triple-A in the Rays system before heading to the Korean Baseball Organization ahead of the 2015 season. He became a star in the KBO, posting a 3.86 ERA and a 1.309 WHIP over 729.2 innings from 2015 through 2018, striking out 641 batters with 206 walks. The Diamondbacks signed Kelly to a two-year deal ahead of the 2019 season, taking a chance on the then-30-year-old despite his having never pitched in the majors.

Merrill Kelly may return to where it all began with the Arizona Diamondbacks

That initial contract turned out to be a bargain as Kelly became a dependable middle-of-the-rotation starter. He ended up spending all but two months of his career in Arizona, posting a 3.74 ERA and a 1.194 WHIP over 953 innings, striking out 865 batters with 290 walks. 

Kelly has been a relatively durable pitcher since returning from the KBO. He has made at least 27 starts in five of his seven years stateside, pitching at least 158 innings in each of those seasons. That durability and ability to eat innings make Kelly a valuable commodity in free agency.

That is especially true for the Diamondbacks. Eduardo Rodriguez and Brandon Pfaadt struggled in 2025 and are currently the top two pitchers on the depth chart. Prospects Kohl Drake and Mitch Bratt, both of whom were acquired for Kelly, should make their major league debuts this season. Kelly would give the Diamondbacks a steady presence that their rotation needs as they build toward the future.