Who is new Yankees reliever Junior Fernández?

While Aaron Judge and to a lesser extent Anthony Rizzo have dominated the Yankees hot stove this winter, the bullpen entered the postseason a bit of a question mark. Although the loss of Zack Britton and Aroldis Chapman to free agency isn’t exactly a loss — and may even be counted as an improvement — the current relief corps of Clay Holmes, Wandy Peralta, Jonathan Loaísigia, and Michael King need some reinforcement if the Yankees want to continue having one of the league’s premier bullpens.

Well, it’s not a proven arm, but Brian Cashman began to bolster the bullpen yesterday by claiming Junior Fernández off waivers from the Pittsburgh Pirates. Entering into his age-26 season, Fernández is still a year out from being arbitration eligible and will not reach free agency until after the 2027. But while four years of team control is certainly nice for the front office’s long-term planning, it is his pitch arsenal — and most importantly, the changes he has made to it in 2022 — that should get Yankees fans excited.

Since making his major league debut in 2019 with the St. Louis Cardinals, with whom he signed as an international free agent in 2014, Fernández has changed up his repertoire a few times. In 2019, he threw his changeup slightly more (31.7 percent) than his slider (26.5) and sinker (26.1), with his fastball coming in a distant fourth (15.6). In just three innings in 2020, he leaned on his fastball, throwing it a whopping 55.7 percent of the time, while abandoning his sinker completely. 2021 saw him reduce his fastball usage slightly to 43.3 as he was primarily a fastball/changeup pitcher who threw a slider with some consistency. Across those three years, Fernández did not look like a major league pitcher, as he posted a 6.62 ERA (5.45 FIP) and 1.78 WHIP in 35.1 innings.

Then, in 2022, Fernández reinvented himself. Not only did he bring back the sinker he had abandoned, he turned it into his main weapon. Now averaging 98.7 mph with an average launch angle of -2 degrees, it was thrown 42 percent of the time. He threw the slider almost twice as much as he did in 2021 (up to 35.1 percent from 21.2), while reducing his four-seam fastball and changeup to pitches that he just peppered in (12.6 and 10.2 percent, respectively).

The results speak for themselves. Although his 2.41 ERA in 18.2 innings is a bit of mirage — he had a 5.79 FIP, 1.607 WHIP, and 14.3 BB% — he has morphed into...well, the exact kind of pitcher that the Yankees have turned into gold with pitching coach Matt “King Midas” Blake.

A lot of pitchers throw sinkers, but how many can hit triple digits with it? Not many — in fact, only five pitchers had a faster sinker than Fernández did in 2022.

Obviously, a fast sinker does not guarantee success (see Chapman, Aroldis), but Brusdar Graterol and José Alverado were at worst competent middle relievers. Jonathan Loáisiga, meanwhile, ranks in at 13th on this list with an average sinker of 98 mph, while Holmes’s 97 mph ranks 30th; and we all know that, when healthy, the list of relievers better than them is very short indeed.

None of this, of course, means that Fernández will follow in the footsteps of Holmes and become a lockdown reliever after leaving the Pirates for the Yankees, and chances are, the team will look to add at least one more reliever over the course of the winter. Even so, he fits perfectly in the mold of Matt Blake reclamation projects, and thus represents a great first step as the Yankees look to bolster their bullpen for 2023.