Great family practice today!!! ????@zebra.h

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Serena Williams is busy as can be in London ahead of the grass-court Slam. She practiced at Wimbledon with her sister Venus on Saturday, and then went with Meghan Markle to watch Prince Harry play charity polo at the Audi Polo Challenge. 

"I enjoyed polo. It was really fun," Serena said on Monday. "It's an intense sport. I feel like they're going sometimes 45 miles an hour. I didn't know this at all. For me it's very scary. Wow, it's very respectable. I feel like every time I watch a new sport, I get so much new respect for it."

Serena's husband, Alexis Ohanian, came along as well. 

Serena, who was seeded No. 25 by the Wimbledon seeding committee, began her campaign for an eighth Venus Rosewater Dish on Monday with a straight-set win against world No. 105 Arantxa Rus. 

Going into the Slam, the 23-time major champion was 5-2 on the season, and had won her previous 14 matches at the All England Club, dating back to 2015. 

Her older sister Venus, a five-time champion and 2017 finalist, played her first round on Monday, too, against Johanna Larsson. She needed three sets to advance. 

Serena takes on qualifier Viktoriya Tomova next, while Venus will play Alexandra Dulgheru.

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