Rubuta ci gaba don wannan sakin layi - A farkon kakar 2017, an fitar da Barnes a karo na farko a cikin aikinsa na MLB, a ranar 23 ga Afrilu ta alƙali Andy Fletcher, saboda a bayyane yake yana ƙoƙarin buga Manny Machado na Baltimore tare da farar don mayar da martani ga tsalle mai wuya da Machado ya yi a kan Dustin Pedroia a cikin wasa kwana biyu da suka gabata. Kashegari, Barnes ya sami dakatarwar wasa hudu don "da gangan ya jefa farar a yankin kan Manny Machado". A kakar 2017, Barnes ya yi wasanni 70 na taimako tare da Boston, ya tattara rikodin 7<unk>3, tare da ceto ɗaya, tare da 3.88 ERA da 83 strikeouts a cikin innings da aka jefa. Barnes ya fara kakar wasa ta 2018 a matsayinsa na yau da kullun a matsayin memba na Boston. A lokacin kakar wasa ta yau da kullun, ya bayyana a wasanni 62, ya tattara rikodin 6<unk>4 tare da ERA 3.65 da strikeouts 96 a cikin innings. A cikin postseason, ya yi bayyanar 10 yayin da ya ba da damar yin wasa guda daya a cikin innings kamar yadda Red Sox ya ci gaba da lashe gasar cin kofin duniya
a kan Los Angeles Dodgers.