The Cartier International Polo games are the last big bang of the London summer season, and while England and the Prince of Wales Team lost to Chile and Hurlingham, guests, including Tamara Mellon and David Hasselhoff, who’s starring as Billy Flynn in the West End production of “Chicago,” were still in the mood to party.

“I don’t even ride — I fell off a Shetland pony when I was about five — but I’m a very good spectator,” said Freddie Windsor with a laugh. After the matches were over, he joined his cousins Prince Harry and Princesses Eugenie and Beatrice at the China White party, which raged on until the wee hours.

Other spectators — including Alice Temperley, Camilla Rutherford, Catrina Guerrini Miraldi, Jodie Kidd, Tara Palmer-Tomkinson, Isabella and Yvonne Hervey and Jay Kay — lunched inside a David Collins-designed tent filled with olive branches, clusters of lemons and black fans on the tables. The theme was Latin America.

“England lost, but it was still fun,” conceded Mellon. “For me, polo is all about the summer.”

The previous day, De Beers hosted its annual Diamond Day event at Ascot, where guests included Nicky Oppenheimer, Anthony Oppenheimer, Emily Oppenheimer Turner, Nick Foulkes, Emma Soames, Alec Wildenstein, Lisa Butcher and Luke Marriott.