The Spanish champions' historic win was overshadowed by a series of controversial calls from German referee Deniz Aytekin and he awarded them two penalties on the way to a 6-1 hammering last week to surge into the quarter-finals.

A source with knowledge of the letter confirmed Tuesday media reports about the dossier sent to UEFA president Aleksander Ceferin; UEFA said that it had received a letter from PSG, giving no details of its content.

The source told AFP that the letter was designed to "point out a series of errors" and "errors of judgement" by Aytekin.

Under-pressure PSG coach Unai Emery said in the aftermath of Barcelona's miracle revival from a 4-0 first-leg deficit: "We had chances to make it 3-2 and then the refereeing decisions, I don't know if they were right or not, but for sure they damaged us." 

PSG president Nasser Al-Khelaifi was less forgiving.

"The outcome of the match could have been different with more clear-sighted officiating," he told Le Parisien newspaper at the weekend.

"Everyone saw that Angel Di Maria should have had a penalty that would have made the score 2-3 and kill any suspense. Not to mention that there was no penalty on (Luis) Suarez late in the game (which was awarded)."