Aleksandr Sobolev’s first-half double helped Spartak Moscow to a 2-1 home victory over Serie A leader Napoli on Wednesday which moved the Russians top of their Europa League group.
All four teams can still progress from Group C and the winner of Leicester’s game against Legia Warsaw would replace Spartak at the summit.
After a fast start to the season, Napoli is now winless in three games in all competitions.
Russian international Sobolev gave Sparta the lead with a third-minute penalty before netting again before the half-hour mark.
Eljif Elmas pulled one back for the visitors in the second period, but Napoli could not find an equaliser.
The result:
Group C: Spartak Moscow 2 (Sobolev 3-pen, 28) bt Napoli 1 (Elmas 64) .