Kammala wannan jumla: A Wasannin Olympics na bazara na 2012 a London, Sjöström ya yi gasa a wasanni hudu na mutum, ya kai wasan kusa da na karshe na gasar
50 m freestyle, 100 m freestyle da 200 m freestyle, da kuma kammala 4th a karshe na 100 m malam buɗe ido a cikin lokaci na 57.17. Dana Vollmer ta Amurka ta karya rikodin duniya na Sjöström a cikin wannan tseren. A cikin 2015 duk da haka Sjöström ya dawo da tarihin duniya ta hanyar inganta shi sau biyu a Gasar Cin Kofin Duniya a Kazan.