Padres’ Mason Miller is immaculate

Mason Miller just kept doing the same thing until he had joined one of the most exclusive clubs in baseball.

“It’s not often I get three righties in a row,” he said. “But once we saw the success start, it’s one of those things you don’t go away from it.”

At the start of the eighth inning Wednesday, Miller struck out Jeremiah Jackson on three straight sliders. Then he struck out Ryan Mountcastle on three more sliders. And finally, he struck out Emmanuel Rivera on three sliders.

With that, he had thrown the 121st immaculate inning in MLB history.

If it ain't broke, don't fix it

Mason Miller's immaculate inning came on 9 straight sliders pic.twitter.com/jbSefFaiF6

— MLB (@MLB) September 3, 2025

“One of the other guys said it’s like a perfect game for a reliever,” Miller said. “It’s an awesome accomplishment, something I’m proud of for sure.”

It was the second immaculate by a Padres pitcher, as Miller joined Bryan Lawrence, who also struck out three Orioles batters on nine pitches in 2002.

It was the third time since StatCast began tracking pitches in 2008 that a pitcher threw just one type of pitch in accomplishing an immaculate inning.

The thing about Miller doing it with his slider is that it is not the pitch for which he is known.

That would be his fastball, which averages an MLB-high 101.2 mph and has topped 104 mph five times this season.

“I knew he had the arm,” Padres manager Mike Shildt said. “I didn’t know the slider was as good as it was and the confidence he has in it, coupled with the big fastball.”

An immaculate inning is not as rare as a perfect game, of which there have been just 24. But three strikeouts on nine pitches is far rarer than a no-hitter (326, not including combined no-hitters) or cycle (350).

“You think about it,” Miller said. “Usually guys get through one or two guys. Usually after six is when you start thinking about it a little bit, you tell yourself, ‘Hey, don’t throw a ball.’ If they’re gonna beat me, they’re gonna beat me, but don’t let you beat yourself. … That’s what I was thinking today.”