An off-target Celtic could only draw 0-0 with FC Sion in the first leg of their Europa League play-off.
The Swiss side ignored UEFA and FIFA rules and fielded four ineligible players during the match, a move which may lead to punishment from football's governing bodies.
After a first-half of few chances, Giorgios Samaras squandered a good opportunity after the restart, but headed over the bar.
Sunbstitute Sean Maloney almost gave the Bhoys the lead, but his free kick was well saved by visiting keeper Vanins.
The away side had the ball in the net with 20 minutes to play, but Feindouno was ruled offside.
Celtic travel to Switzerland to play the second leg on Thursday, August 25.