Zenit St Petersburg have been rocked by the news that Italian international Domenico Criscito has been ruled out for at least six months.
Criscito suffered a cruciate ligament tear in a friendly against Siena last Thursday and has been booked for surgery this week to repair the damage.
Zenit boss Luciano Spalletti has confirmed that he will be without the full-back for the rest of this season.
He told the club's official website: "Mimmo (Criscito) tore cruciate ligaments and will need to undergo surgery."
The Russian champions will begin life without Criscito in the first leg of their Europa League last-16 tie with FC Basel in midweek.