Real Madrid coach Carlo Ancelotti said he understands the club's fans booing him and his team in their 5-2 win over Celta Vigo in their last-16 Copa del Rey tie on Thursday, which he sees as an act of frustration after the humiliating 5-2 defeat to Barcelona in the Spanish Super Cup on Sunday.

Ancelotti said he was happy that his team showed character to not be affected by the anger of their fans and advanced to the quarterfinals on Thursday, KosovaPress reported.

"I see it as a wake-up call from the fans for the team and its coach. It's an acceptable wake-up call after what happened in the match against Barcelona. Then the team reacted well," Ancelotti told a press conference.

"The fans abandoned us to give us a wake-up call because the team started to complicate a game that we were on track to win 2-0. But then the fans started to push and when the Santiago Bernabeu pushes it is something very special for us. We played well in extra time and managed to win the game, so everything was good in the end," said the Italian coach.