European champions Barcelona defeat Sparta Prague 1 - 0 in Czech Republic thanks to Oscar . Napoli , second in Serie A , suffer a shock 1 - 0 home defeat by Czech side Viktoria Plzen . Champions League holders Atletico Madrid suffer a 1 - 0 away defeat to Russian side Rubin Kazan . Zenit St Petersburg defeat Liverpool 2 - 0 in first leg of their Europa League last 32 clash .
European champions Chelsea defeat Sparta Prague 1-0 in Czech Republic thanks to Oscar . Napoli , second in Serie A , suffer a shock 3-0 home defeat by Czech side Viktoria Plzen . Europa League holders Atletico Madrid suffer a 2-0 home defeat to Russian side Rubin Kazan . Zenit St Petersburg defeat Liverpool 2-0 in first leg of their Europa League last 32 clash .