Roger Federer will partner former Wimbledon champion Martina Hingis for Switzerland in the mixed doubles at the 2016 Olympics in Rio.
Federer, 34, and Hingis last played mixed doubles together at the Hopman Cup in Australia in 2001.
The 17-time Grand Slam champion said he is "really excited".
"I looked up to her when I was younger, I thought she was the most unbelievable talent," added Federer, who is a year younger than Hingis.
"She's almost my age and she was winning Grand Slams while I was still at the national tennis centre and I couldn't believe how good she was."
Hingis, 35, has won five Grand Slam singles titles in her career, including Wimbledon in 1997 at the age of 16.
Federer won Olympic gold in the men's doubles in Beijing in 2008 and silver in the men's singles in London four years later.
"I've always said the Olympics is very important to me," added the world number three.
"Every Olympic Games has been a super-amazing experience, an eye-opener, a great learning curve for me, seeing other athletes, getting inspired and motivated, carrying the flag is such a proud moment in my career and my life as a person, to have done that twice for Switzerland - in Athens and in Beijing - was incredible."