Aytekin “failed in the performance of his duties”

UEFA have acknowledged that referee Deniz Aytekin “failed in the performance of his duties” during Barcelona's comeback victory against PSG in 2017. The historic comeback, when Barca came back from a 4-0 first-leg deficit to win 6-1 on the night at the Nou Camp, finished with drama and controversy after three late goals sent Barca through. In particular, Luis Suarez winning a penalty, which resulted in Barca's fifth goal in stoppage time, was contentious and UEFA have acknowledged as such, with the referee could reportedly facing potential further penalties. 
UEFA's Disciplinary Committee, as reported by French outlet Onze Mondial, said Aytekin “failed in the performance of his duties” on 8 March 2017 in the Champions League round-of-16 clash. European football's governing body considered a demotion for the referee, and the French club also lodged a formal complaint outlining all the mistakes of Aytekin that night. It is unknown why the complaint took three years to be handled and the admittance will not come as any consolation to PSG players and fans. That year, Barcelona were knocked out in the quarter-finals by a Juventus side who would go on to lose in the final to Barca's fierce rivals Real Madrid. PSG have not gone beyond the round-of-16 since, losing to Real Madrid in 2018 and Manchester United last season. 

Source: Daily Mail