Almost 21,000 fans attended the match at the Belgrade Arena, which was filled with flags supporting Russia, along with banners displaying anti-NATO messages. Fans also chanted their support for Russia during the game, which Zalgiris won 86-80.
Zalgiris announced on Friday that all revenue from ticket sales for their next home match on Sunday, against Utenos Juventus in the national league, will be donated to Ukrainian causes.
"Having repeatedly shown its strong position regarding military aggression in Ukraine, the Kaunas Zalgiris organisation continues to seek to help Ukrainians fighting for their freedom," the club said in a statement.
Lithuania has been one of Ukraine's staunchest supporters since Russia launched its invasion in February 2022.
EuroLeague and Red Star have been approached for comment.