Russia have received a huge setback after CSKA Moscow midfielder Alan Dzagoev was ruled out of Euro2016 with a broken metatarsal bone.
The news will come as a boost to Russia's Group B rivals – England and Wales. Slovakia are the fourth member of the group.
The 25-year-old suffered the injury during CSKA's 1-0 win over Rubin Kazan on Saturday.
Krasnodar's Dmitri Torbinski will replace Dzagoev in the squad for the Euros.
"This is a big loss for us. It's sad because he was in great form," RFU president Vitaly Mutko told the TASS news agency.
"Dzagoev will be replaced by Torbinski. He's a great guy and a great player."