Roger Federer says he'll be teaming up with Martina Hingis for Switzerland in mixed doubles at next year's Rio Olympics.

Federer wrote Friday on Twitter that he is "really excited" about the pairing, and posted a photo of the two tennis stars from what he said was 15 years ago.

Federer is 34, Hingis is 35.

Federer owns a record 17 Grand Slam singles titles. He also owns two Olympic medals: silver in singles at London in 2012, and gold in doubles with Stan Wawrinka at Beijing in 2008.

Hingis owns 20 major titles — five in singles, 11 in women's doubles, four in mixed doubles — and is a member of the International Tennis Hall of Fame. She retired from singles but still competes in doubles, winning women's and mixed titles at the U.S. Open in September.