Bellingham and several Read Madrid team-mates approached the referee after full-time at Allianz Arena
Real Madrid's Jude Bellingham says the decision to send off team-mate Eduardo Camavinga during their 4-3 Champions League loss to Bayern Munich was "a joke".
Substitute Camavinga, who was only on the pitch for 24 minutes, was shown a second yellow card in the 86th minute for kicking the ball away and delaying a Bayern free-kick following a foul on Harry Kane.
As Bellingham walked past reporters on his way to the team bus in Munich, he was asked about the late dismissal that proved pivotal to the result of the quarter-final second leg.
"A joke," he said in Spanish, shaking his head as he continued on. "Impossible that it is a red."
With Wednesday's tie level on aggregate at 4-4 the time, the decision left Real to see out the closing stages with 10 men, as Bayern scored two late goals to win 6-4 on aggregate and progress to the semi-finals.
It ruined the game - Arbeloa
England midfielder Bellingham was not alone in his frustration. Several Real players reacted strongly both during and after the match.
Defender Antonio Rudiger hinted his disapproval but stopped short of direct criticism.
"It's best I don't talk about the referee. Did you see the red card?" he told the media.
Club captain Dani Carvajal, who did not feature in the match, confronted referee Slavko Vincic from the touchline following the incident.
Television footage showed him shouting angrily and pointing towards the official after Camavinga's dismissal.
"It's your fault," Carvajal is seen shouting.
Arda Guler, who scored Real's first two goals, was given a red card in the aftermath of the defeat after storming over to the referee.
He wrote on Instagram after the game: "This isn't how it should've been. We're very sorry. We will be back. Hala Madrid."
Guler will now miss the first game of next season's league phase.
Manager Alvaro Arbeloa said the sending-off "obviously" decided the match, insisting: "You can't send a player off for something like that.
"Nobody understands how a player can be sent off for that.
"I think the referee took out the card because he did not know Camavinga was booked already, because it was up to Bayern's players to go and tell him it was the second card.
"It's a double mistake besides not knowing he already had a yellow. It ruined a match that was going really well, very evenly matched. It was at its peak. That was the end of the game."
Spanish journalist Juan Castro described the mood of those at Real as one of disbelief.
"People are very angry at the referee," he said. "They are very worried about what has happened in Munich. This will have consequences.
"The second yellow card to Camavinga, you cannot give it in a Champions League match at that moment, when both teams are level. You cannot give it.
"You could see all the players going against the referee. From Madrid's perspective, that decision shifted the balance to Bayern Munich."
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Luis Diaz's thunderous strike came shortly after Camavinga's sending off, putting Bayern 5-4 ahead on aggregate before Michael Olise's sublime curler flew in off the post in the 94th minute to put the tie beyond doubt.
Speaking after the match, Diaz said he had a clear view of the Camavinga incident and backed the referee's call.
"I think the referee was right to send him off. We wanted to take the free-kick quickly and he didn't release the ball.
"Obviously, the red card really lifted our spirits and we said 'This has to be it - this is the moment', and that's exactly how it turned out.
"Games like this are decided by small details but we were already pushing and creating chances."
Bayern goalscorer Harry Kane focused on the importance of the win.
"Obviously the sending off helped us a little bit but we had to take our moments at the end of the game and with Lucho [Luis Diaz] and Mike [Olise], we did that."
European football governing body Uefa said its disciplinary body will review the referee's report before deciding whether any further action is required.
Bayern will face Paris St-Germain in the semi-finals, while the 15-time winners' exit is likely to be overshadowed by controversy around one of the defining decisions of the tie.
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