Meghan Markle breaks maternity leave to receive Red Sox and Yankees team shirts for Archie at baseball game with Prince Harry

With a surprise heatwave and a two-month-old baby, Meghan Markle would have been forgiven for wanting a chilled evening at home in Frogmore Cottage.

But the Duchess of Sussex, 37, delighted royal fans everywhere with her stylish appearance at the Boston Red Sox versus New York Yankees baseball game in London last night.

The new mum - who is understood to be the middle of her three-month maternity leave - beamed as she arrived at the London Stadium in Stratford with Prince Harry.

They left son Archie at home in one of their first outings since becoming parents for the first time.

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Despite the 33 degrees Celsius temperatures, Meghan kept her cool in a chic little black dress by British designer Stella McCartney.

The Duchess also ensured she was comfy in a pair of Aquazzura Deneuve ballet flats in black suede.

She finished off her elegant ensemble with blow-dried, wavy hair and natural make-up.

On her left hand, could be spied the gorgeous eternity ring given to her by the Duke of Sussex, 34, to mark their first wedding anniversary recently.

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The couple met both opposing American teams in the Major League Baseball event.

Each side gave them a personalised present for Archie.

Meghan grinned as the Yankees handed her a team T-Shirt bearing ‘ARCHIE 19’.

She looked just as delighted when the Red Sox presented her with a red baby-gro.

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Meghan and Harry, who were stepping out in support of the Invictus Games Foundation, chatted and laughed with the players.

However, at one point the American-born royal shared a warm embrace with Red Sox outfielder Mookie Betts.

They are distantly related “cousins” and shared ancestors in Alabama 150 years ago, according to the Boston Globe.

Before the game started, the Duke and Duchess walked onto the pitch in front of approximately 60,000 baseball fans.

It is the third time Meghan has been seen in public since giving birth.

She previously appeared with Archie and Harry at Windsor Castle just days after he was born, and she also joined fellow royals at Trooping the Colour earlier this month.