Cika jumla mai zuwa: Kalniņš ya cancanci
maza 100 m freestyle, a matsayin memba na tawagar Latvian yin iyo, a 2012 Summer Olympics a London, ta hanyar eclipsing wani FINA B-misali lokaci na 50.18 seconds daga Turai Junior gasar zakarun Turai. Ya kalubalanci wasu masu iyo bakwai a zagayen na huɗu, gami da dan wasan Paraguay dan asalin Burtaniya Benjamin Hockin. Kalniņš ya yi tsere zuwa matsayi na biyu, kuma ya nutse a ƙarƙashin shinge na dakika 50 da kwata na biyu (0.25) a bayan Kemal Arda Gürdal na Turkiyya, a cikin mafi kyawun sa na 49.96. Kalniņš ya kasa ci gaba zuwa wasan kusa da na karshe, yayin da ya sanya na talatin a gaba ɗaya a cikin wasan farko.