The Duke of Cambridge was among the mourners paying their respects to his former polo tutor at a memorial service on Monday.
Prince William, 39, attended a service of thanksgiving for Claire Tomlinson at St Mary's Church in Tetbury, Gloucestershire.
The trailblazing polo player passed away at the age of 77 on 13 January. The Duke was among around 200 friends and family members at Monday's service.
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Claire was the first woman to compete against men on equal terms in the male-dominated sport and coached the English national team she once captained.
She was so well regarded that the Prince of Wales asked her to teach his sons how to play polo at the Beaufort Polo Club. William and Harry have continued to be avid polo players and have competed against one another in charity matches.
Prince William pictured with Claire Tomlinson in 2000
Claire was the first woman in the world to reach five goals in 1986, as well as the first to win the County Cup in 1972 and the Queen's Cup in 1979. She still holds the women's high-goal handicap record today.
Her children are all polo players and compete internationally. The Duke and Duchess of Cambridge and Prince Harry attended Mark Tomlinson's wedding to Laura Bechtolsheimer in the Swiss resort of Arosa in 2013.
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Claire with Charles and Harry in 2009
According to the Daily Express, those leaving the memorial service for Claire said it was an "amazing" and "beautiful" tribute to one of the world's greatest players.
A statement from the Hurlingham Polo Club on 13 January read: "The HPA is very sad to learn of the death of Claire Tomlinson at the age of 77. Claire died peacefully at home with her children by her side.
"Claire was the first woman player to reach 5-goals and was a trailblazer for women players around the world. She was an innovative and inspiring coach to many generations of players, including coaching England teams at every level, as well as a polo pony breeder and trainer of immense renown.
"She will be sorely missed by all who knew her, but her legacy will live on through her children and grandchildren at the Beaufort Polo Club. Our thoughts are with the family."
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