Rubuta ci gaba don wannan sakin layi - A Wasannin Olympics na bazara na 2000 a Sydney, Muller ya yi gasa a cikin wasanni huɗu na iyo. Ta sami matsayin FINA A na 25.94 (50 m freestyle), 55.82 (100 m freestyle), da 2:00.35 (200 m freestyle) daga Nationalasashen Afirka ta Kudu a Johannesburg. A cikin taron farko, 200 m freestyle, Muller ta kammala wasan kusa da na karshe tare da lokaci na tara na 2: 00.04. Tun da farko a cikin prelims, ta buga na biyu mafi sauri lokaci da kuma Afirka ta Kudu rikodin na 1: 59.89. Kwana uku bayan haka, a tseren mita 100 na 'yanci, Muller ya kammala na shida a wasan karshe tare da kyakkyawan tarihin Afirka na 55.19. A tseren mita 50 na 'yanci
, Muller ya sanya lokaci na 26.07 daga zafin rana tara, amma ya rasa wasan kusa da na karshe da kashi 11 cikin dari na biyu. A ranar ƙarshe ta shirin, Muller ya sake haɗuwa tare da Loots, Sarah Poewe, da Charlene Wittstock a cikin 4 × 100 m medley relay. Yin iyo a cikin freestyle leg, Muller ya kafa tseren tare da raba 54.77, sabon rikodin kasa, amma 'yan Afirka ta Kudu sun zauna ne kawai a matsayi na biyar a cikin lokaci na 4:05.15.