HOUSTON — Astros starting catcher Yainer Diaz is going on the injured list after sustaining an oblique injury during batting practice prior to Monday’s 8-3 loss against the Dodgers, manager Joe Espada said.

Diaz, who was scheduled to start, was scratched about an hour before first pitch and was replaced by backup Christian Vázquez.

Through an interpreter, Diaz said his oblique “bothered me” after taking a swing in batting practice. He had not undergone imaging as of Monday night and did not know anything about his short-term prognosis.

Though Diaz had not been officially placed on the IL, the team still summoned catcher César Salazar from Triple-A Sugar Land to provide insurance for Monday night’s game. Infielder Shay Whitcomb was optioned as a corresponding move.

Diaz’s injury came just as the 27-year-old catcher had started to emerge from an early-season offensive funk. Over his past 47 plate appearances, he had a .754 OPS, a stretch in which he struck five extra-base hits.

Vázquez should assume everyday duties in Diaz’s absence, but the team could be wary of overexposing a 35-year-old who played only 65 games in 2025. Salazar, 30, got beaten out by Vázquez in spring training for the backup catcher job.

Salazar was DFA’d in March, but passed through waivers unclaimed and returned to the Astros’ organization, where he is beloved for his game-calling and personality.