Liverpool take on Sparta Prague in the UEFA Europa League Round of 16 tonight – but one player is not actually allowed to feature. Jurgen Klopp takes his side to the epet ARENA – where the Reds attempt to clear the first hurdle of the knockout phase and eventually send the German off with a first ever UEFA Europa League title. So, which Liverpool player is not allowed to feature against Sparta Prague? Let’s take a look… Why Trey Nyoni cannot play for Liverpool against Sparta PragueWell, Trey Nyoni made his Liverpool debut in the recent 3-0 FA Cup win over Southampton. Klopp was always unlikely…