Martina Hingis has rejoined Switzerland's Fed Cup team after a 17-year absence in a bid to qualify for next year's Olympic Games in Brazil.
The five-time Grand Slam singles champion has been selected for the Swiss squad to face Poland in the World Group play-off on 18-19 April.
The former world number one must play in the women's team competition to become eligible to compete in Rio.
Hingis, 34, has not played Fed Cup since the 1998 final defeat to Spain.
Roger Federer, the 17-time major winner, said in March that he had given "some thought" to Hingis' request to play mixed doubles in Rio, but may opt to concentrate on the singles and men's doubles tournaments.
Hingis now concentrates exclusively on doubles tennis, and is the current holder of the Australian Open mixed doubles title, with Leander Paes, and the Indian Wells and Miami women's doubles titles with Sania Mirza.
Hingis will be joined in the Swiss squad by Timea Bacsinszky, Stefanie Voegele and Viktorija Golubic.