Russian striker Pavel Pogrebnyak remains an uncertain starter for the European Championships following a knee injury in a friendly match against Serbia on Wednesday, dpa reported.
The Zenit St Petersburg forward will undergo a further examination on Tuesday after suffering a small cartilage tear in his left knee, team officials said.
Russia face a final test before Euro 2008 on Wednesday against Lithuania in the German town of Burghausen.
The Russians, coached by Dutchman Guus Hiddink, are in a training camp at Rottach-Egern, south of Munich, and open their Euro campaign against Spain on June 10 in Innsbruck, Austria.
Russia defeated Serbia 2-1 on Wednesday, with Pogrebnyak opening the scoring in the 12th minute before suffering the injury three minutes later.
The loss of 24-year-old Pogrebnyak, who was the UEFA Cup's joint leading scorer with Bayern Munich's Luca Toni this season, would by a major blow to the team which will miss Pogrebnyak's team-mate Andrei Arshavin in the first two group games over a suspension.
It would also be another setback for the player who missed the UEFA Cup final victory over Glasgow Rangers through suspension.
Russia's other opponents in Group D of the June 7-29 tournament in Austria and Switzerland are title-holders Greece and Sweden.