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.
COMMENT RULES: Comments that are judged to be defamatory, abusive or in bad taste are not acceptable and contributors who consistently fall below certain criteria will be permanently blacklisted. The moderator will not enter into debate with individual contributors and the moderator’s decision is final. It is Belfast Telegraph policy to close comments on court cases, tribunals and active legal investigations. We may also close comments on articles which are being targeted for abuse. Problems with commenting? email@example.com