Kammala jumla mai zuwa: A farkon kakar 2018, a wasan 11 ga Afrilu da New York Yankees a Fenway Park, Kelly ya buga Tyler Austin da filin wasa, bayan wani zane na Austin wanda aka zarge shi da yin wasa da Brock Holt. Austin ya zargi Kelly kuma ya fara gwagwarmaya; 'yan wasa hudu, ciki har da Kelly, an fitar da su. Wannan shi ne karo na farko da aka kori Kelly. A ranar 12 ga Afrilu, MLB ta dakatar da Kelly na wasanni shida kuma ta ci tarar da ba a bayyana ba; daga baya ya daukaka kara, yana ba shi damar ci gaba da wasa har sai an kammala tsarin daukaka kara. A ranar 26 ga Afrilu, an ki amincewa da roko na Kelly, ma'ana cewa dakatarwarsa za ta fara aiki daga wannan lokacin. A lokacin da aka dakatar da shi, Kelly ya kalli wasa daga kujerun masu kallo a Fenway Park. Ya bayyana a cikin wasanni 73 mafi girma na Red Sox, ya gama da 4.39 ERA a cikin innings. A cikin postseason, Kelly ya yi wasanni tara, yana jefa innings yayin da yake ba da damar yin wasa daya kuma ya buga 13. Shi ne dan wasan da ya lashe, a cikin taimako, na Game 4 na
Gasar cin Kofin Duniya, yayin da Red Sox suka doke Los Angeles Dodgers a wasanni biyar.