Kammala jumla mai zuwa: Cahill ya zira kwallaye a wasan farko a kakar wasa ta bana a wasan da suka yi nasara da Reading a ranar 22 ga Agusta 2012. A ranar 31 ga watan Agusta, ya zira kwallaye a gasar zakarun Turai.
2012 UEFA Super Cup da Atlético Madrid, wanda Chelsea ta yi rashin nasara 4-1. A ranar 5 ga Disamba, 2012, Cahill ya zira kwallaye na farko a gasar zakarun Turai ta UEFA, inda ya kara da Nordsjælland a wasan gida 6-1. A ranar 16 ga Disamba, 2012, an kori Cahill daga wasan da ya buga da Corinthians a wasan karshe na gasar cin kofin duniya na kungiyoyin kwallon kafa na 2012 FIFA da Chelsea ta yi nasara da 1-0 bayan wani rikici da Emerson. A watan Janairun 2013, Cahill bai fito a wasan da suka yi da Stoke City ba saboda haihuwar dansa, Leo. A ranar 15 ga Mayu, ya fara wasan karshe na UEFA Europa League na 2013 da Benfica kuma ya yi muhimmiyar matsala ta ƙarshe a cikin lokutan ƙarshe don tabbatar da cewa Chelsea ta lashe wasan 2<unk>1.