In a high-pressure moment that could define his early tenure in San Diego, flamethrower Mason Miller slammed the door on the Diamondbacks Wednesday night with an electrifying ninth inning, notching his first save as a Padre in a 3-2 win at Chase Field.

Just 24 hours after surrendering a game-tying homer on a 103.9 mph heater, Miller bounced back with a vengeance. The 25-year-old struck out the side in the bottom of the ninth, navigating around a two-out walk and freezing Adrian Del Castillo with three straight pitches to end the game — the last of which exploded past the plate at 103 mph.

“Mason was nasty,” Padres manager Mike Shildt said postgame. “That’s the guy we traded for.”

The game was a late-inning chess match — and the Padres, behind GM A.J. Preller’s deadline wizardry, had the right pieces. Trailing 2-1 in the ninth, Ryan O’Hearn launched a game-tying homer off lefty Kyle Backhus, his first dinger off a southpaw all season. Xander Bogaerts doubled, Jake Cronenworth bunted him over, and Jose Iglesias roped a full-count single to right to drive him in.

“We just stayed in the fight,” O’Hearn said. “And Mason slammed the door. That’s what closers do.”

Mason Miller shuts the D-Backs down amid Padres comeback victory

San Diego Padres pitcher Mason Miller (22) pitches against the Arizona Diamondbacks during the ninth inning at Chase Field.
Joe Camporeale-Imagn Images

The win secured a series victory for the Padres, who now sit just two games behind the Dodgers in the NL West. San Diego trailed in 20 of the 29 innings played in this series, yet emerged with two gritty wins.

It was a statement moment for Miller — and a vindication for Preller’s aggressive deadline play. After being initially rebuffed by the A’s, Preller offered a package centered on top prospect Leo De Vries to acquire Miller and lefty JP Sears. Now, the Padres have an elite closer locked down through 2028.

Miller’s rebound performance silenced doubts after Tuesday’s stumble.

“Sometimes you get beat with your best stuff,” Miller said. “But I trust it. I’m gonna keep bringing the heat.”

The Diamondbacks, meanwhile, were left stunned. Corbin Carroll’s 443-foot blast in the first and Alek Thomas’ sac fly in the second were all they could muster. After the second inning, Arizona’s offense managed just one hit.

Their bullpen — depleted and unsteady — couldn’t hold on. Backhus, who earned a two-inning save on Monday and bailed Arizona out of the eighth on Wednesday, couldn't repeat the magic in the ninth.

San Diego, however, used high-leverage arms like Jason Adam, Adrian Morejón, and finally Miller to shut things down.

With an off day ahead, the Padres have momentum — and a flamethrowing closer who just made a powerful first impression.

“It’s just the beginning,” Miller said, with a smirk.