The count has begun as musician Pitbull aims to set the Guinness World Record for the largest gathering of people wearing bald caps.
If the count is deemed legitimate, it is hoped the Latin hip hop artist, 45, will be awarded a certificate shortly before his British Summer Time (BST) Hyde Park headline set on Friday evening, after a count which began at about 5pm.
Taking to the stage wearing a white vest top, black tie and a bald cap ahead of the official 60-second count, BBC Radio 1 presenter Greg James said: “Today, thousands of you are about to take part in an official Guinness World Record.
“This could, it be could be the largest gathering of people wearing bald caps that’s ever taken place in the history of the world, ever, ever, ever.
“And we would love to present Mr Three Oh Five, Mr Worldwide, check it in, check it out, Dale with a certificate to say that he is a world record holder today but that relies on all of you taking this very seriously.”
If the count goes off without issue, the gig will set the record, as one currently does not exist for the feat.
James added: “Quickly though, are there any actual bald people here?
“You do need, sir, you do need a bald cap on your bald head for this to count. You will not be counted.
“I know you’re bald and I know you’ve gone through a lot, but this won’t count.”
It comes after fans began a trend of attending Pitbull’s concerts dressing up as him, sporting suits, aviator glasses and bald caps.
The trend has gone viral in recent years, with videos of audience-packed arenas full of bald-cap wearing fans singing his songs back at him.
Prior to Friday’s gig, the singer and festival organisers had appealed for volunteers to count bald caps in the crowd.
Supermarket chain Aldi also supplied 300 caps to Mr Worldwide fans outside the London park and temporarily rebranded itself as “Baldi”.
The rapper is among the roster of headliners performing at the festival this year, following on from shows by US band Maroon 5, folk pop group Mumford And Sons and an upcoming set from Scottish singer Lewis Capaldi.
Miami-born Pitbull is best known for the songs Fireball, Timber, Time Of Our Lives, On The Floor, Give Me Everything, Feel This Moment and Don’t Stop The Party.
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