After setting career-highs in wins (13), ERA (3.37), and innings pitched (200.1) last season, Merrill Kelly has been one of the best performing foreign-born pitchers in the major leagues this year.
This season, Kelly has the most wins in the National League (NL) (8-3) and is even better than last season, when he posted a career-best 2.92 ERA, 82 strikeouts in 77 innings pitched, and a 1.10 WHIP (walks allowed per inning pitched).
Considered a fifth starter when he was acquired ahead of the 2019 season, Kelly’s ace-like performance since last year has been hailed as a “stroke of genius” by Arizona, who signed him to a three-year, $25 million extension in April.
ML’s best armoury, Kelly evolves from innings-eater to K-machine
A big reason Kelly, now in his fifth season in the majors, has exceeded expectations is his ability to confuse hitters with a variety of pitches in all corners of the strike zone.
From his major league debut in 2019 to last year, all five pitches in his arsenal – fastball, sinker, cutter, changeup, and curveball – have been at or above a 10 per cent ground ball rate. This season, he added an outside slider to his repertoire against right-handed hitters, making him one of the most versatile pitchers in the league.
Kelly doesn’t just throw a variety of pitches, he throws them in the right places at the right time. Kelly’s style of pitching, which utilises all areas of the strike zone, has been credited with creating a lot of confusion in the minds of opposing hitters.
In addition, this season, he has begun to throw his fastball family (four-seam, sinker, and cutter) more often than he has in the past.
Kelly’s three fastballs and changeup were previously praised for their excellent tunneling effect (the synergistic effect of different pitches forming similar trajectories). However, the more varied patterns of his fastballs have allowed him to confuse hitters even more, which in turn has greatly improved his changeup’s ability to induce swings. (34% career-high changeup swing rate this season).
As a result, Kelly’s strikeouts per nine innings have increased significantly this year to 9.6 (career average is 8), and this season he has become more than just an innings-eater, but a complete ace with excellent strikeout ability.
Constant work on his pitches has paid off with a reverse-export success story 먹튀검증
Kelly was a pitcher who constantly worked to improve his pitches in the KBO, whether it was increasing the velocity of his fastball or honing his cutter, and he continued to do so in the major leagues.
In 2019, his rookie season in the majors, Kelly’s changeup had a small amount of vertical movement that was 15cm lower than the average changeup of other pitchers with similar conditions (release point and velocity).
This season, however, the changeup has seen a significant increase in vertical movement, with Kelly’s changeup posting over 7cm more vertical movement than the league average, and this improvement has made his changeup one of the most powerful in the league (changeup FIPS comparison: .906 in Season 19 / .352 in Season 23).
In addition to his changeup, Kelly’s work on improving his pitches is clearly paying off, as his cutter’s rising movement and sinker’s drop have both improved by more than 5 cm since his rookie season (Season 19/23 wOBA: .767 / .536 for cutter, .859 / .675 for sinker).
Kelly’s leap to the top of the ML starting rotation this season is likely to be an inspiration to many foreign players, including Eric Peddy, who is currently on a tear in the KBO, winning 10 games in the shortest amount of time in the league’s history.
Meanwhile, Kelly’s performance has also helped his club, Arizona, defy pre-season expectations and lead the National League West by four games over the Los Angeles Dodgers.
With a 20-win season on the cards at this rate, it will be interesting to see if the ‘hard-working genius’ can maintain his reputation as one of the league’s best starters at the end of the season and lead his team to both a district title and a postseason berth.