Rubuta ci gaba ga wannan sakin layi - Fognini ya fara kakar 2015 a gasar cin kofin Hopman
, abokin tarayya Flavia Pennetta. Italiya ta kasa kaiwa wasan karshe, inda ta kammala a karshen rukunin su. Makon da ya biyo baya, ya buga a Apia International Sydney a matsayin dan wasa mafi girma, amma ba shi da sa'a don jawo zakara Juan Martín del Potro, wanda ke dawowa daga watanni goma sha ɗaya na rauni, a wasan farko. Ya yi rashin nasara a wasanni uku. Fognini ya lashe Grand Slam na farko a gasar Australian Open ta 2015 tare da Simone Bolelli, tare da cin nasara a kan Pierre-Hugues Herbert da Nicolas Mahut a wasan karshe. Ya doke Rafael Nadal a wasan kusa da na karshe na Rio Open kafin ya yi rashin nasara a wasan karshe da David Ferrer. A watan Afrilu, ya sake doke Rafael Nadal a zagaye na uku na Barcelona Open, amma ya sake rasa a zagaye na gaba zuwa Pablo Andujar. A watan Mayu, bayan ya ci Steve Johnson da Grigor Dimitrov, ya yi rashin nasara a Tomáš Berdych a zagaye na uku na Masters na Rome. A US Open, Fognini ya doke Steve Johnson da Pablo Cuevas don ci gaba zuwa zagaye na uku inda ya haifar da babbar damuwa, ya doke Rafael Nadal a cikin saiti biyar, yana zuwa daga saiti biyu da hutu na aiki a duka saiti na uku da na huɗu. A wannan wasan, Nadal ya lashe saiti biyu na farko, kuma a baya ya kasance 151<unk>0 a wasannin Grand Slam wanda ya jagoranci saiti biyu zuwa babu. Samun nasara 70, Fognini ya ƙare ya doke Nadal a cikin saiti biyar. Daga baya ya rasa wasan zagaye na huɗu da Feliciano López.