Diamondbacks Opening Day Starter Continues to Ramp Up vs Giants

The Arizona Diamondbacks are at Scottsdale Stadium on Saturday to take on the San Francisco Giants in Cactus League action.

The Giants have the best win-loss ratio in Arizona, with a 15-5 record and a +41 run differential (126-85). The Diamondbacks are 9-12 with a -43 run differential (102-145), and have especially struggled with pitching and defense this spring.

Zac Gallen Continues to Ramp Up

Feb 18, 2026; Scottsdale, AZ, USA; Arizona Diamondbacks pitcher Zac Gallen (23) poses for a photo for MLB media day at Salt River Fields at Talking Stick. Mandatory Credit: Allan Henry-Imagn Images | Allan Henry-Imagn Images

Diamondbacks opening day starter Zac Gallen will get the ball for the D-backs. He threw three perfect innings on March 9, needing just 41 pitches to navigate the outing. Look for him to get the fourth up-down and expand that pitch count up to 55 pitches in this outing.

After this outing, Gallen will have one more spring start to get to five innings and somewhere around 70 pitches. That means he will probably be limited to no more than 85 pitches on opening day against the Dodgers, and perhaps less.

It's not ideal, but it's the best the Diamondbacks can do in this situation. Merrill Kelly was originally tabbed to be the opening day starter, but Intercostal Nerve Irritation in his back set him back and he is likely to start the year on the injured list.

Four right-hand relievers are among the pitchers expected to appear in Saturday's tilt, including Joe Ross, Kevin Ginkel, Ryan Thompson, and Juan Morillo. Sunday's starter will be Brandon Pfaadt, who is expected to follow Gallen in the rotation order in Los Angeles.

Right-hander Adrian Houser will start for the Giants. Houser is entering his 10th season in MLB. The long-time Milwaukee Brewer signed as a free agent with the Giants in December.

Diamondbacks Lineup

Saturday at Scottsdale Stadium. pic.twitter.com/BVv24tQQw9
— Arizona Diamondbacks (@Dbacks) March 14, 2026

The D-backs' lineup features four players from the 40-man roster. As of this writing the team is still waiting for news about Gabriel Moreno's forearm tightness. James McCann will work with Gallen again, a pairing we can expect to see the majority of Gallen's starts in the regular season, regardless off Moreno's health.

Corbin Carroll is back at the top of the order in the DH slot as he continues to race back from hamate bone surgery. Jordan Lawlar is in center field again. It's notable that Alek Thomas has not played in a game yet since Mexico was eliminated from the World Baseball Classic

The entire D-backs starting infield of Carlos Santana, Ketel Marte, Geraldo Perdomo (all for DOM) and Nolan Arenado (PUR) are still playing WBC games.