Ryu Hyun-jin has made his return from elbow surgery about a year and two months ago, and he’s been pitching so well that it’s almost negated the time away.
As of Sept. 19, Ryu has started nine games and is 3-3 with a 2.62 ERA.
It’s his best start since the 2020 season (5-2, 2.69 ERA in 12 games – a shortened season due to COVID-19), when he finished third in the American League Cy Young Award voting.
Ryu’s curveball has been a key factor in his successful rehabilitation after undergoing Tommy John surgery to repair ligament joints in his elbow.안전놀이터
■ Slow, timing-stealing curveball, effective against lefties…free to change velocity
Ryu’s average velocity (110 km/h), lowest velocity (100 km/h), and highest velocity (115 km/h) on his curveball against Boston.
With a fastball velocity (142.5 km/h on average) that ranks in the bottom 2% of the majors, Ryu’s main weapon is his changeup (23.1% of pitches thrown), which allows him to capitalize on changes in velocity.
This season, however, his curveball (17.6%) has been just as effective as his changeup.
Against right-handed batters, he utilizes his changeup as his deciding pitch, and against left-handed batters, he utilizes his curve (22.5% against lefties), which is slower than his four-seam fastball (46.8% against lefties).
While his four-seam fastball only averages 142.5 km/h, the 40+ km/h difference in velocity between it and his slower curveball, which can reach as low as 100 km/h, works synergistically to take away lefties’ timing.
Against lefties, Ryu’s four-seam fastball has a whopping .071 BABIP (14-for-1).
His curveball has a .222 BABIP (9-for-2).
The velocity of his curveball can vary from as low as 100 km/h to as high as 115 km/h, confusing hitters.
Ryu has been described as a “master of the art of pitching” due to his precise delivery and unpredictable mix of pitches.
Comparing the two tables below, we can see that this season, he is using a wider range of velocity variations than in previous years, which is helping him succeed.
Ryu’s velocity distribution in 2023 (horizontal axis: velocity, vertical axis: frequency of velocity) *Source: Baseball Servant
Distribution of Ryu Hyun-jin’s pitches in 2022 (horizontal axis: pitch speed, vertical axis: frequency of pitch speed) *Data source: Baseball Servant
■ Another ‘secret weapon’ is the sinker…unsealable and fun against right-handed hitters.
Ryu’s other secret weapon this season has been his sinker.
A type of two-seam fastball, the sinker is a little slower than a four-seam fastball, but it curves in the direction of the throwing hand.
For a left-handed pitcher, it curves to the outside of right-handed hitters, and Ryu uses his fifth-pitch sinker (10 percent of his pitches) to induce misses like a changeup.
Ryu’s BABIP on his sinker this season is 0.167 (12-for-2).
This is the lowest BABIP of the five pitches Ryu has used this season.
Both of his two walks have been singles, so he’s been able to keep long balls down.
The location of Ryu’s sinker this season (from the batter’s perspective) is concentrated outside of the right-handed batter’s box.
Ryu used his sinker through the 2020 season before virtually sealing it in 2021.
In 2022, he didn’t use it at all.
This was due to his triple-digit walk rate (10% walk rate and .389 BABIP in 2022).
This season, however, he’s reintroduced the sinker into his arsenal, and it’s been effective against right-handed batters, albeit at a lower walk rate and strikeout rate.
This is likely due to improved horizontal movement (lateral change).
According to Baseball Servant, Ryu’s sinker has 2.2 inches more horizontal movement this season than the league average.
This ranks 21st out of 260 pitchers in the majors with a sinker.
This change in sinker movement gives Ryu multiple options to win battles with hitters.