Bryce Miller stays historic through five starts

Bryce Miller bump day is becoming a synonym for MLB history being made. Miller made his fifth career start Wednesday, going six innings, giving up two hits and striking out six to just one walk in a 6-1 win over the Athletics.

His totals are up to 31.1 innings pitched, going 3-1 with a 1.15 ERA. He has given up just 13 hits, striking out 28 and walking just three. His 1.87 FIP, 335 ERA+ and 0.511 WHIP points to his dominance is well earned. 

That 0.511 WHIP is the lowest mark through the first five career starts of any pitcher’s career in MLB history. He is also the first pitcher since 1901 to go more than six innings and give up four hits or less in his first five appearances.

He has also put up a game score above 70 in four of five starts, a mark of an above-average start. His first five-game scores are 74, 72, 74, 56 and 73, meaning he has yet to make a bad start. His average of 69.8 is the 43rd-highest average in MLB history but the third-highest since 1988. 

With a nasty fastball and slider combo, Miller’s only pitch with negative outcomes has been his curveball. His fastball, especially, has been his out pitch, being responsible for 22 of his 28 strikeouts. 

His fastball spin rate is in the 99th percentile of the league, according to baseball savant, being a massive part of his success starting his career. 

Against that pitch, hitters are hitting .108 and slugging just .135. Against his slider, they are hitting .071 and slugging .143. Combining those two pitches to the curveball, there is a night and day difference, as hitters are hitting .364 and slugging .455 against that curveball. 

A major factor in the dominance of those pitches has been his ability to generate spin but alter his active spin between the two. With the fastball, the pitch is generating a 2608 spin rate at 95.1 MPH with 87% active spin and 19.1 inches of movement. Compared to the slider, which generates a 2407 spin rate at 86.2 MPH with 24% active spin and 3.4 inches of movement. 

With both pitches coming from a 6.3-foot extension, his deception is rivaled by very few in the game. Notably, his fastball has already generated a run value of -8, tied for the 21st-best pitch of the 2023 season with one of the highest usage rates among pitches that have generated that good of a value. 

While it has just been five starts, he already sits comfortably as one of the best pitchers of the 2023 season. He ranks in the 83rd percentile of hard-hit percentage, 92nd percentile in expected ERA, 84th percentile in expected batting average, 98th percentile in walk rate and 79th percentile in chase rate. 

His 1.4 WAR means that through five starts, he has almost already proven himself to be a serviceable start over the course of a full season. Another stat of record-breaking proportion from the arm of Miller has been his 1.1 win probability added, the second-highest mark from a Mariners player in their first five career appearances.