(CNN) -- Tennis great Serena Williams and Reddit co-founder Alexis Ohanian are engaged.

A spokesperson for Ohanian confirmed that he popped the question while the two were vacationing in Rome. Williams first announced the news herself in a Reddit post on its "r/isaidyes" forum.

"I came home/A little late/Someone had a bag packed for me/And a carriage awaited" Williams said in her Reddit post, which was written like a poem and had a cartoon of the couple at the top. "Destination: Rome/To escort me to my very own 'charming'/Back to where our stars first collided/And now it was full circle/At the same table we first met by chance/This time he made it not by chance/But by choice/Down on one knee/He said 4 words/And/r/isaidyes."

Ohanian also announced the engagement on his Facebook page, linking to Williams' Reddit post and adding, "She said yes."

Williams and Ohanian, who have been dating since the fall of 2015, have mostly kept their romance out of the spotlight, though she does post pictures of them on her Instagram account from time to time.