Tomas Necid is set to spend "several months" on the sidelines after the CSKA Moscow and Czech Republic striker was told he needs a second operation on ruptured knee ligaments.
Zenit St Petersburg are within touching distance of their second successive Russian Premier League title after a 2-0 win over nearest challengers CSKA Moscow.
FIFA.com previews the remainder of the Russian season, which resumes this weekend following the winter break, with Zenit St Petersburg in pole position to defend their title.
The top of the Russian Premier League table became congested after CSKA were held to a 1-1 draw by Kuban Krasnodar, and Zenit St Petersburg beat Spartak Moscow 3-0.
Zenit St Petersburg were held to a 2-2 draw by Ruin Kazan, while CSKA Moscow moved within two points of the top after a 2-1 win over Rostov, and Spartak edged Krylya Sovetov 1-0.
Rubin Kazan lost their first game of the season at Anzhi Makhachkala, Zenit St Petersburg were held 2-2 at ten-man Spartak Nalchik, while CSKA Moscow drew 1-1 at home to Krasnodar.