<p>Gallen's potential free-agent departure looms over the rotation, elevating the need for multiple reliable arms and a clearer path at the fifth starter. The D-backs must plan for life after Gallen while maximizing Rodriguez and Pfaadt during the interim.</p>

Gallen faced Tatís’ grand slam in a critical late‐season matchup. A top late‐season starter, his command and velocity are central to Arizona’s plan, and the Tatís slam adds to his matchup notes as opponents adjust to San Diego’s recharged offense in October.

Gallen yielded six runs on seven hits plus three walks in a rough start that could mark the end of a long Diamondbacks’ ace era, as he nears free agency with a career-worst ERA this season.

Gallen will start Friday after illness/fatigue, signaling a rotation shake-up while Arizona hunts a must-win stretch. His return is pivotal for the D-backs’ expectations down the stretch.

Gallen, Arizona’s potential playoff catalyst, is listed to start Friday as the D-backs chase a wild-card spot, with the rotation framed by high-stakes performances late in the season.