On Tuesday night, Barcelona returned to the scene of their shock defeat to Celtic in last season's Champions League and left Parkhead with a highly controversial 1-0 victory.
With the score at 0-0 in the 59th minute, Celtic captain Scott Brown was shown a straight red card by French referee Stephane Lannoy after bringing down Barca's summer signing Neymar.
But many onlookers were left questioning whether Brown deserved to be sent off, claiming that Neymar's reaction had helped the referee to come to the conclusion that a yellow card was not sufficient. Lannoy's interpretation, though, appeared to be that Brown had had a little kick at the Brazilian after his original challenge and deemed the contact to be worthy of a straight red.
With Cesc Fabregas going on to net the only goal of the game, the incident proved to be the turning point of a match which had seen Celtic offer stiff resistence for most of the opening hour and the Scottish side's boss Neil Lennon was left fuming by the dismissal.
So was a red card the correct outcome for a cynical foul by Brown, or was the exaggerated reaction of Neymar the telling factor in the referee's decision? Vote now in our Goal poll to have your opinion heard.