Could the Diamondbacks bring back former ace Zac Gallen? MLB insider says there’s a chance

Key Highlights

• Several other free-agent starting pitchers still on the market, and those arms could influence Gallen’s next destination. Apr 13, 2025; Phoenix, Arizona, USA; Arizona Diamondbacks pitcher Zac Gallen (23) reacts after the end of the second inning against the Milwaukee Brewers at Chase Field.
• Mandatory Credit: Allan Henry-Imagn ImagesAdvertisementAdvertisementAdvertisementOnce a Cy Young Award candidate, Gallen has struggled to recapture that form over the past two seasons, with 2025 proving to be his most difficult year in Arizona.
• The former Diamondbacks ace finished the season with a career-worst 4.83 ERA, along with a 1.26 WHIP and 175 strikeouts. Despite showing flashes of improvement late in the year, Gallen’s inconsistent performance for much of the season may have limited his ability to secure the type of contract he was seeking. That raises the question: could the Diamondbacks make a splash and bring back their former ace, even at the cost of a draft pick?Sep 9, 2025; San Francisco, California, USA; Arizona Diamondbacks starting pitcher Zac Gallen (23) throws a pitch against the San Francisco Giants during the first inning at Oracle Park.
• Mandatory Credit: Robert Edwards-Imagn ImagesAdvertisementAdvertisementAdvertisementThe potential on-field value could outweigh that price.
• FanGraphs projects Gallen to produce 2.4 WAR in 2026, a meaningful contribution for a rotation that will almost certainly require additional depth. With a potential Gallen return, the rotation becomes both clearer and more competitive.