Antonio Rudiger has apologised after appearing to throw an object at referee Ricardo De Burgos Bengoetxea during Real Madrid's Copa del Rey final defeat to Barcelona, with a lengthy ban now likely.

Madrid's best chance of salvaging silverware from a disappointing season was dashed on Saturday as they lost 3-2 to their Clasico rivals in extra time in Seville.

The build-up to the game was overshadowed by Madrid questioning the integrity of De Burgos, who broke down in tears in an emotional press conference on Friday.

After De Burgos lashed out at Madrid's treatment of officials, Los Blancos suggested the Spanish FA (RFEF) should change the referee and had to deny reports they were considering a boycott of the game.

More controversy followed in the dying moments of the final as Rudiger – who had been substituted by Carlo Ancelotti – reacted angrily to the award of a Barcelona free-kick.

He appeared to throw an object – believed to be an ice pack – in the direction of De Burgos from the technical area and was shown a red card, with Lucas Vazquez and Jude Bellingham also receiving red cards after full-time.

Under RFEF guidelines, Rudiger could be banned for between four and 12 games if the incident is deemed "mild violence", while he could be suspended for up to a year if a disciplinary committee deems the incident was an "assault against referees".

Rudiger has now taken to social media to apologise for his behaviour, writing on X: "There's definitely no excuse for my behaviour last night. I'm very sorry for that.

"We played a very good game from the second half on – after 111 minutes I was not able to help my team any more and before the final whistle I did a mistake. 

"Sorry again to the referee and to everyone I disappointed last night."

Ancelotti refused to comment on the officials in his post-match press conference, while saying Rudiger was taken off due to being "exhausted" in extra time.

Madrid have courted controversy with their treatment of match officials on several occasions this season, including when the club wrote a letter of complaint to the RFEF in February, claiming decisions were "rigged" against them.

The widespread abuse directed at Jose Munuera Montero after he showed Bellingham a red card for dissent in February's 1-1 draw with Osasuna in LaLiga, meanwhile, was described as "repulsive" by the RFEF. 

On Friday, LaLiga president Javier Tebas hit out at Madrid – and their president Florentino Perez – in an extraordinary rant on X.

He wrote: "This is not football, it is control of power. After the statements of the referees – fed up with the constant harassment from Real Madrid TV – he responds as he knows.

"He suspends the press conference. He skips training at La Cartuja. He despises the officials of the Copa final. He leaks that Madrid are not going to appear in the final of the Copa.

"He does not protest, he pressures. He does not complain, he threatens. He does not disagree, he punishes. He doesn't want to improve football, he wants his football."

Madrid's final chance to avoid a trophyless season is now in LaLiga, where they trail Barca by four points with five matches remaining.