Serena Williams is reportedly dating a 20-year-old tennis player after several sightings of the pair going for "romantic" strolls.

The tennis star is ten-years older than Bulgarian Grigor Dimitrov but that hasn't stopped the pair embarking on a whirlwind romance.

According to the NY Post, Serena was spotted out with Grigor in Paris on Monday and then went for a cosy lunch at restuarant L'Avenue and then went to tourist hotspot the Eiffel Tower before going for a romantic stroll near to where Serena has an apartment.

"They were laughing and seemed to really enjoy each other’s company. It looked like a first date," the source said.

What do you think of this couple?

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