Enrique Iglesias and Anna Kournikova Pose for Rare Photo Together

The former tennis pro shared the pic on Instagram.

Anna Kournikova and Enrique Iglesias have been dating since 2001, and on Thursday, they posed for their first Instagram photo together.

Kournikova shared a pic of herself and Iglesias with her brother, Alan Kournikova, and captioned the image with a few sweet emojis.

The 35-year-old tennis pro and the 41-year-old singer sparked romance rumors after she starred in his music video for "Escape." The two have never confirmed or denied their relationship, and it has been speculated that the two secretly wed, given the huge ring Kournikova wears on her left hand.

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On May 22, she posted a video on Instagram of her dancing to Iglesias' new song, "Duele El Corazon," and her big yellow diamond is in plain view.

In 2012, Iglesias spoke about his feelings toward marriage to Parade magazine. "I’ve never really thought marriage would make a difference. Maybe it’s because I come from divorced parents, but I don’t think you love someone more because of a piece of paper," he explained. "And nowadays, it’s not taboo to have kids and not be married. What makes a difference is that you’re a good parent, period."

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Kournikova shared a similar sentiment with Women's Health in 2011. “It isn't important to me,” she said of marriage. “I’m in a happy relationship -- that’s all that matters.”

Another couple to keep their relationship status mum is Bristol Palin and Dakota Meyer, who confirmed this week to ET confirmed that they secretly married. Here's a look at the newlyweds' romantic timeline: