Madrid - Real Madrid have been thrown out of the Spanish Cup after fielding an ineligible player in their tie against third-tier side Cadiz, the Spanish Football Federation (RFEF) confirmed on Friday.
In the first leg of their fourth-round tie on Wednesday Russian international Denis Cheryshev not only started the match but also opened the scoring in Madrid's 3-1 win.
But he shouldn't have been on the field as he was due to serve a one-match ban in the cup after picking up three yellow cards whilst on loan at Villarreal last season.
The federation's competition committee judge ruled that "Cheryshev was ineligible to play ... so Madrid have forfeited the game and the tie is resolved in favour of Cadiz."
Real Madrid, Europe's richest club, were also slapped with a fine of $6 520. The club has 10 days to appeal.
In a statement, Real said the ban could not have taken effect as Cheryshev did not know he was suspended.
"The competition judge acknowledges that Cheryshev was not personally notified about his ban," the club said.
"Real Madrid C.F...can verify the acknowledgement that the Spanish Football Federation did not personally notify Cheryshev about his ban, which is the only way the ban can take effect.
"We at Real Madrid C.F. stand by our argument and will take the appropriate action to ensure that the final outcome is favourable for the club."
The statement came after Real president Florentino Perez insisted at a press conference on Thursday that the his club "is not at fault" and should not be disqualified from the competition.
He said Real did not receive a list from the federation drawn in July of all the players who were under the threat of a suspension for the season.
"Nobody told the club or the player, not the federation nor Villarreal, so it was impossible for us to act differently," Perez said.
He also argued that according to the club's interpretation of the competition's by-laws, previous bookings are voided at the start of the round of 32.
The federation's judge dismissed Perez's arguments, saying in his ruling that it was "implausible" that the player did not know that he was sanctioned.
"There is no doubt that the sanction of suspension was notified personally to the player," he said.
The head of the Spanish league, Javier Tebas, earlier on Friday said he felt the possible disqualification of Real Madrid over the affair "seemed a bit disproportionate".
Earlier this season, Spanish football saw second-division Osasuna booted out of the cup in an almost identical case.
And in 2001, Real coach Rafael Benitez was in charge of Valencia when they were thrown out of the same competition for fielding four non-EU players when only three were permitted.
Real took Cheryshev, who is usually on the fringes of the first team, off right at the start of the second half when they apparently realised their error but Cadiz filed an official complaint.
Benitez said the club wanted to "show good faith".
Cadiz issued a statement after the federation issued its decision, saying it "can do nothing more than regret all that has happened."
"At no time did the club want to be the protagonist in the Copa del Rey tie, beyond the celebration that it represented for our city to host one of the most important football clubs in the world," the statement added.
The controversy comes during a roller-coaster season for Real.
They comfortably qualified for the Champions League last 16 but are third in La Liga on 27 points, six behind leaders Barcelona and two back from city rivals Atletico in second.
"It is a long road," Benitez told a news conference earlier on Friday ahead of the club's league match at home against Getafe on Saturday.
"We are doing better than what many people think and we have to prove that on the pitch in every game," he added.
He declined to comment on the controversy over the use of Cheryshev, saying Perez had given a "sufficiently reasonable explanation".
Real Madrid have won the Spanish Cup 19 times, with their last success in 2014.