She was accompanied by Kate Middleton, who attended with 1-year-old Prince Louis in tow.
Her two older children, Prince George, 5, and Princess Charlotte, 3, are also said to have been in attendance, according to reports.
The sisters-in-law watched from the sidelines at the Billingbear Polo Club in Wokingham, England. The royal brothers are playing to compete for the Khun Vichai Srivaddhanaprabha Memorial Polo Trophy at the sporting match.
Each duchess worked their own distinctive styles at the summer event.
Meghan wore an olive green smock dress with large aviator style sunglasses from Givenchy.
Kate, meanwhile, wore a pink, short-sleeved tea dress, which she paired with a contrasting red Mulberry bag and a pair of sunglasses perched atop her head.
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