William, whose wife the Duchess of Cambridge is due to give birth to their first child, looked relaxed as he played in a team alongside his brother, Prince Harry.
Wearing a purple and white number four shirt, the future king chatted to well-wishers during breaks in play at the Jerudong Trophy at Cirencester Park Polo Club in Cirencester, Gloucestershire.
William got on the scoresheet to give his team a half-time lead, but the princes ended up losing the game 5.5 to 7.
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