As the then Duke of Cambridge (now Prince of Wales) presented the FA Cup trophy to Liverpool after their victory over Chelsea at Wembley Stadium in May, some fans booed the royal.
As many spectators cheered, Prince William presented the cup - decked with red ribbons - to Liverpool captain Jordan Henderson.
It was handed from player to player before manager Jurgen Klopp joyfully held the trophy above his head, his first in the competition.
But the occasion wasn’t all smiles: earlier, some fans in the crowd were heard booing as William shook hands with players ahead of kick-off.
So why did fans boo the royal?
Here is everything you need to know.
As he walked onto the pitch before the FA Cup final at Wembley, Prince William was booed by sections of the crowd.
The jeering began when the Duke of Cambridge, the Football Association’s president, was introduced during the BBC’s pre-match coverage.
The booing grew as William made his way down the pitch, meeting and shaking hands with Chelsea and Liverpool players before the game began.
The national anthem and a rendition of the Christian hymn ‘Abide With Me’ also seemed to enrage some supporters in the stadium, as both were also booed.
According to the Daily Mail, while the Prince stood singing ‘God Save the Queen’, fans gesticulated and made obscene hand gestures.
The B Positive Choir, whose members have sickle cell disease or have close friends or family members who do, sang ‘Abide With Me’.
The Duke of Cambridge seemed unconcerned at the jeers, but MPs have spoken out against the behaviour of spectators at the stadium.
Sir Ed Davey, leader of the Liberal Democrats, said: “We have the most wonderful Monarch and those fans who booed do not represent their clubs or our country.”
Tory MP and former Culture Secretary Karen Bradley said: “It is utterly unacceptable and disg”aceful that fans booed Prince William. I would urge the FA to take all necessary action and pursue those responsible.’
Why did fans boo?
The source of the majority of the booing is unknown, though observers have speculated that it was primarily Liverpool fans, according to the Daily Mail.
Liverpool fans “are well known” for booing ‘God Save The Queen’ at Wembley, according to Connor O’Neill, football writer for the Liverpool Echo.
When Liverpool played Chelsea in the Carabao Cup final at Wembley earlier this year, there were similar accusations of fans booing the national anthem.
O’Neill said the reasons for doing so stem from the city’s hatred against Margaret Thatcher’s Tory government in the 1980s.
He said: “The Conservative Government’s ‘managed decline’ of the city was then followed by the failings of the Government following the Hillsborough disaster, which further entrenched those feelings.”
The residents of Merseyside have continued to feel let down by the state in recent years, and believe foodbanks outside Anfield and Goodison Park (the home ground of Liverpool and Everton respectively) are proof of rising disparities.
The tense connection between city and country extends to the English national team, with many Liverpudlians refusing to support England at key competitions such as the Euros or the World Cup.
A flag that reads “scouse not English” is frequently seen at Anfield, and will most likely continue to be on show at most games.
Howard Beckett, a trade unionist who ran for general secretary of the Unite union last year, hailed Liverpool fans for "rejecting blind patriotism and the establishment," calling the outburst "pure quality."