Real Betis Coach Gabriel Calderon revealed his disbelief at the decision to award a penalty to Rubin Kazan.
Betis were a goal up through Didac Villa with Rubin down to 10 men when Belgian official Serge Gumienny signalled for a spot kick, even though Lolo Reyes’ challenge appeared to be outside the area.
Roman Eremenko duly converted to give Rubin a valuable away goal and leave Calderon angry at the officiating.
“The linesman was in a position to see it clearly,” Calderon said after the match.
“Everyone in the stadium could see it. The referee has an obligation to see it. If everyone else has seen it then so has he.
“He’s changed the outcome of the game, given them a gift and that isn’t fair.
“It’s like being given a goal that isn’t a goal, helping them get through to the next round.”
Calderon however backed his players to get a positive result in the return leg, although warned they will have to adapt to the conditions quickly.
“We’ve still got a chance because we can score in the away leg,” Calderon continued.
“We know we can win that game. We’re not used to the cold and the pitch there but we will have to adapt to get through.”