Rubuta ci gaba don wannan sakin layi - Williams ya fara kakar 2015 ta wakiltar Amurka tare da John Isner a gasar cin kofin Hopman
Ka yi haƙuri. 'Yan wasan Amurka sun yi rashin nasara a wasan karshe da Poland. A gasar Australian Open Williams ta doke Maria Sharapova a karo na 16 a jere don da'awar ta 6th Australian Open singles title da kuma 19th aiki Grand Slam singles title, lashe take a kan ta uku wasan batu a na biyu sa. Tare da wannan nasarar Williams ta zarce duka biyu, Evert da Navratilova, don na biyu mafi yawan taken Grand Slam guda daya da aka ci nasara a cikin Open Era. Sunan kuma shine taken ta na shida na Grand Slam tun lokacin da ta cika shekaru 30, uku fiye da na gaba mafi kusa da yin hakan (Margaret Court, Martina Navratilova tare da uku kowannensu). Ita kadai ce 'yar wasa a tarihi da ta lashe duka Grand Slams guda hudu a kalla sau daya bayan ta cika shekaru 30. A karshen mako mai zuwa, Serena da 'yar'uwarta Venus sun yi tafiya zuwa Buenos Aires don fuskantar Argentina a wasan rukuni na II na duniya don Fed Cup. Ta buga kuma ta ci wasan ta kawai da María Irigoyen don taimakawa Team USA zuwa nasarar 4-1 a kan Argentina. Williams ta ba da sanarwar cewa za ta yi gasa a Masters na Indian Wells wanda ke kawo karshen shekaru 14 na kauracewa taron. Bayan dawowarta, Williams ta sami farin ciki daga taron kuma ta lashe wasan farko a madaidaiciya. Ta kai wasan kusa da na karshe, inda za ta fuskanci lamba ta 3, Simona Halep, don samun wuri a wasan karshe, amma an tilasta mata janyewa saboda raunin gwiwa. Ta hanyar cin nasarar Sabine Lisicki a wasan kusa da na karshe na Miami Open, Williams ta zama mace ta takwas kawai a cikin Open Era don yin rikodin nasarar wasan 700 a cikin aikinta. Wannan kuma ya sa ta zama ɗaya daga cikin 'yan wasa uku masu aiki da suka ci wasanni 700 ko fiye a wasan kwaikwayo, wasu kuma Roger Federer da Rafael Nadal. A wasan kusa da na karshe ta yi nasara a kan Halep don ci gaba zuwa wasan karshe na goma a taron inda ta lashe lambar yabo ta takwas kuma ta kara yawan nasararta zuwa 21 ta hanyar doke Carla Suárez Navarro.