William was on the opposite team to his brother, Prince Harry, at the event held at musical impresario Andrew Lloyd Webber's Berkshire estate.
The match was played at Andrew Lloyd Webber's estate
The Kent and Curwen Royal Charity Polo Cup was held in aid of Sentebale and the Tusk Trust charities, which the Princes support.
Harry's team won
Harry's team won the game with a last-minute goal, and he was awarded the most valuable player award.
Meanwhile bookmakers Coral said the odds on Kate giving birth tomorrow had shortened from 5/1 to 4/1 after a flurry of bets.