Ka cika wannan magana: A Wasannin Olympics na shekara ta 2012 a Landan, Agnel ta ci lambobin yabo guda uku: zinare biyu da azurfa ɗaya. A cikin wasansa na farko, Agnel ya kafa wani ƙoƙari na dawowa daga baya a cikin tseren tseren mita 4 × 100 don lashe zinare tare da Amaury Leveaux, Fabien Gilot, da Clément Lefert. Da yake nutsewa tare da raunin 0.55 s, Agnel ya iya yanke wannan zuwa raunin 0.30 s a alamar mita 350. A cikin mita 50 na ƙarshe, Agnel ya ja gaba da Ba'amurke Ryan Lochte kuma Faransa ta ci nasara da lokacin 3:09:93 zuwa lokacin Amurka na 3:10:38. Agnel ya yi iyo mafi saurin lokaci a cikin dukkan filin tare da lokaci na 46.74, mutum ne kawai ya karya 47 seconds. Kashegari, Agnel ya lashe lambar zinare ta biyu a tseren mita 200 tare da lokacin 1: 43.14, mafi sauri a tarihin iyo na Faransa da sakan 1.79 a gaban wadanda suka lashe lambar azurfa Sun Yang da Park Tae-hwan. A wasan karshe, Agnel ya jagoranci daga farawa zuwa gamawa, yana yin rikodin lokaci na 50.64 a cikin mita 100 na farko da 52.50 a cikin mita 100 na ƙarshe. Lokacinsa na 25.98 na mita 50 na karshe ya kasance mafi sauri a fagen. Agnel ya lashe lambar yabo ta karshe, ta azurfa, a tseren tseren mita 4 × 200 a bayan Amurka tare da Amaury Leveaux, Grégory Mallet, da Clément Lefert. Yana da mafi saurin raba lokaci na filin a wasan karshe tare da lokaci na 1:43.24 a matsayin kafa na anga. A gasarsa ta karshe,
A tseren mita 100, Agnel ya gama na huɗu a cikin mafi kyawun lokacinsa na 47.84, 0.04 s na biyu a waje da lambobin yabo. Kungiyar Wasannin Wasannin Turai ta zabi Agnel a matsayin dan wasan Turai na shekarar 2012.