Pedzisa mutsara unotevera: Pamakwikwi eOlympics yeZhizha ya2012 muLondon, Sjöström akakwikwidza mumitambo mina yega yega, achisvika kuma semi fainari emamita makumi mashanu akasununguka, 100 m akasununguka uye 200 m akasununguka, uye achipedza 4th mufainari ye
100 m butterfly munguva ye57.17. Rekodhi yenyika yaSjöström yakaputswa munhangemutange iyi naDana Vollmer wokuUnited States. Muna 2015 zvisinei Sjöström akadzorera rekodhi yenyika nekuivandudza kaviri paWorld Championships muKazan.