San Francisco, California, USA; Athletics pitcher Mason Miller (19) reacts to walking in the winning run against the San Francisco Giants during the tenth inning at Oracle Park. D. Ross Cameron-Imagn Images

Athletics' Mason Miller Racking Up Strikeouts at Historic Rate Despite Struggles

Originally posted on Fastball on SI | By Sam Connon | Last updated May 25, 2025 9:39 AM ET

When Mason Miller burst onto the scene in 2024, he looked like the best closer in the game.

Miller's nasty stuff has still been on display at times in 2025, but the Athletics certainly haven't been reaping the rewards in the same way they did last season.

The 26-year-old right-hander took the mound in the ninth inning of Saturday night's showdown with the Philadelphia Phillies, looking to preserve a 6-5 lead and bring his team's 10-game losing streak to an end. Miller racked up three strikeouts that inning, but not before he gave up a game-tying solo home run to Max Kepler.

The A's went on to lose 9-6 in extra innings after Miller fell victim to his second blown save this season.

In 18 games this year, Miller has gone 0-2 with a 6.11 ERA, 1.415 WHIP and 11 saves across 17.2 innings of work. And yet, he has still managed to rack up 35 strikeouts in that time, leading all qualified MLB pitchers with 17.8 strikeouts per nine innings.

According to Underdog Fantasy's Justin Havens, Miller is now one of three relievers in the Wild Card Era to record at least 35 strikeouts in 20.0 or fewer innings while boasting an ERA over 6.00 across an 18-appearance span. Houston Astros righty Josh James was the last to achieve the odd feat, doing so in 2019, while Boston Red Sox righty Matt Barnes established the club in 2018.

RP with 35+ K and 6+ ERA in 20 or fewer IP across an 18-appearance span in Wild Card Era

Mason Miller (2025)
Josh James (2019)
Matt Barnes (2018) https://t.co/1DwGX8vWwI
— nugget chef (@jayhaykid) May 25, 2025

Miller was well on his way to AL Rookie of the Year honors before he hit the injured list for nearly a month last summer. He ended the season 2-2 with a 2.49 ERA, 0.877 WHIP, 14.4 strikeouts per nine innings, 28 saves and a 2.5 WAR.

Just looking at his ability to create whiffs, Miller seems to still have that high-level stuff in his repertoire. And even amid Miller's struggles to get outs, the A's are still 13-5 when he takes the mound this season compared to 9-26 when he doesn't.

But for Miller to recreate the kind of season he strung together in 2024, he is going to need to stop issuing walks and allowing abnormally loud contact.

The Athletics and Phillies are set to close out their series in West Sacramento at 4:05 p.m. ET on Sunday. Miller hasn't pitched in back-to-back games since April, so it remains to be seen if he will be available out of the bullpen.

This article first appeared on Fastball on SI and was syndicated with permission.

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