Mukunoki debuted for the Buffaloes on July 7, 2022, against the Saitama Seibu Lions, where he allowed 2 hits, threw 7 strikeouts, and did not allow a run.[1] In just his 2nd game against the Hokkaido Nippon-Ham Fighters, he was throwing a no hitter, when in the bottom of the 9th, with only 1 out to go, gave up his no-hitter on a single by Fighters infielder Ryusei Sato.[2] Buffaloes closer Yoshihisa Hirano took over from there and struck out Kensuke Kondo to earn his 24th save.
