Mason Miller’s Immaculate Inning: Bigger and Weirder

In the eighth inning of Wednesday’s 7-5 loss to the Orioles, Padres reliever Mason Miller threw an immaculate inning — nine pitches, three strikeouts. Immaculate innings are rare, but not that rare. Since 2005, we’ve seen 63 immaculate innings in the majors, so around two or three per season. Miller’s is the fourth of 2025, after Cal Quantrill on May 18, Brandon Young on July 8, and Andrew Kittredge on August 6. Immaculate innings are a special treat we get to enjoy from time to time. They happen infrequently enough that they do genuinely feel special, but not so infrequently that every single one demands an article memorializing the event.

Another special treat that I’ve enjoyed recently is attending a concert with my best friend. We don’t live within driving distance of one another, so due to logistical barriers, we’ve only done this four times in the last 10 or so years. So like an immaculate inning, it’s a cool thing that doesn’t happen very often. What makes our concert history extra special is that twice now touring artists have scheduled shows on my birthday — Tame Impala’s Currents Tour in 2016 and Weird Al’s Bigger and Weirder Tour this year. And what makes Miller’s immaculate inning extra special is that he threw nothing but sliders. Trust me, you’ll see how these two things are connected in a minute, but first more about all those sliders.

If you know anything about Mason Miller, it’s probably that he fires fastballs past hitters at roughly 2,700 giga-miles per hour, which means you know that his primary pitch is not a slider — it’s his fire-breathing fastball. This season Miller is throwing his slider around 45% of the time and his fastball the other 55% of the time, with the very occasional changeup sprinkled in. In his major league career, Miller has appeared in 146 innings in which he has faced at least three batters. He had not gone Oops! All Sliders in any of them prior to Wednesday. And he only topped 65% sliders in four of those innings. His next-highest single-inning slider ratio is 85%, thrown in the final inning of a start against the Mariners in May of 2023. His slider-heavy final frame was the capper on a seven-inning no-hit outing.

But the all-slider approach isn’t just unusual relative to Miller’s typical usage, it’s also strange within the historical context of immaculate innings too. Going back to 2005 (when the easily accessible data tagged with pitch types starts), no other immaculate inning has featured sliders exclusively, or any other secondary pitch for that matter. And just two have consisted entirely of fastballs. On March 30, 2019, then Brewers closer Josh Hader downed the Cardinals on nine sinkers, and on June 15, 2022, while pitching for the Astros, Phil Maton threw an immaculate inning against the Rangers using just his four-seam fastball. And prior to Miller, the most sliders thrown in an immaculate inning was eight: Ross Ohlendorf of the Pirates did that in the seventh inning of an eight-inning start against the Brewers on September 5, 2009. No one has thrown seven sliders in an immaculate inning, and only twice has a pitcher thrown six sliders to achieve the feat.

OK, back to the concerts. Both times that Travis (aforementioned bestie) and I went to a concert on my birthday, we got to our seats midway through the opening act. We didn’t do it on purpose. The first time we got stuck in traffic on the way to the venue. (Red Rocks, and yes, I am bragging about seeing Tame Impala at Red Rocks on my birthday.) The second time we were waiting in line for merch. (I am now the proud owner of a Weird Al tour poster!) Some unexpected circumstances plunged our plans into shallow chaos and the result was a strange confluence of outcomes nearly a decade apart.

Just as arriving late to a concert not once, but twice was unusual for us, throwing eight of nine pitches outside the zone is highly unusual for Miller, but nevertheless, that’s how it went down for him on Wednesday afternoon in San Diego. The most erratic Miller has ever been (in an inning with at least three batters and nine pitches) was in the bottom of the ninth on May 14, 2024 in Houston. Just three of his 13 pitches landed in the zone. He was still effective, getting two strikeouts and a lineout, but those results were despite his wildness, not because of it. He got just two whiffs on pitches outside the zone. That’s not to say that Miller is the second coming of Greg Maddux. Far from it, actually. Miller’s Zone% this season sits at 48.2%, which ranks 146th among qualified relievers, so he’s prone to get a little wild. But Wednesday’s outing was wild even for him.

Yet out of that chaos was born a beautiful result. And as we emerged out of the havoc that led to our late concert arrivals, we too were treated to an oddly beautiful outcome. Both times we found ourselves watching an opener play with a montage of video clips and photos all featuring a well-known male actor. Mac DeMarco played in front of looping footage of Kelsey Grammer, and Puddles Pity Party covered Celine Dion and Metallica with a highlight reel of Kevin Costner in the background. Neither Grammer, nor Costner seemed connected in any way to the music played by the artists. Perhaps they explained what was happening at the start of the set. We’ll never know. But somehow, a Canadian singer-songwriter and a baritone cabaret clown from Atlanta both chose the same visual gimmick (that I have only run across in these two instances) for shows played on my birthday, but in different states, nine years apart.

I have no idea how I stumbled into that situation once, let alone twice, nor do I understand how Miller got eight swinging strikes when he couldn’t hit the ocean from a boat. Typically, Miller can get hitters to chase on 34.0% of pitches outside the zone, but on this day they whiffed at 87.5% of the pitches he threw outside the zone. Miller’s career swinging strike rate, whether pitches are in the zone or not, is 17.6%. And his best whiff rate in a single inning (minimum three batters and nine pitches) had been 45.5% before Wednesday, a mark he’d hit twice — once on September 6, 2024 against the Tigers, and again on April 27 of this year against the White Sox.

As for whether any other immaculate innings can match Miller’s whiff rate or inability to find the zone, the answer is no. No they cannot. Two candidates were nearly as wild, missing the zone with seven pitches and falling just shy of Miller’s eight. Iván Nova managed it while pitching in relief against the Mets on May 29, 2013, as did Astros reliever Will Harris on September 27, 2019 versus the Angels, but Nova only got four swinging strikes and Harris just two. No one else has managed eight whiffs, but Hader’s immaculate inning from 2019 included seven. However, just three of Hader’s pitches missed the zone. The closest facsimile to Miller in terms of both zone avoidance and swinging strikes was Max Scherzer, pitching for the Dodgers in a game against the Padres on September 12, 2021. In the top of the second, Scherzer threw just three pitches in the zone, but managed six swinging strikes, leaving him two pitches behind Miller in both categories.

Miller has been a prime candidate to throw an immaculate inning since the day he debuted, so it’s not all that surprising that he finally got it done. And as previously stated, not every immaculate inning is deserving of the full article treatment. But other times, Puddles the Clown tricks Weird Al into kissing him on the mouth the day after Puddles the Oregon Duck goes briefly headless during player intros, and then later that same week Mason Miller throws an immaculate inning composed of nine sliders, one pitch in the strike zone, and eight whiffs. And wouldn’t it just be a shame if we didn’t stop for a moment and wonder at the majesty of it all?