Roger Federer has recovered from his back injury and will play in the Davis Cup final, which starts on Friday.
The Swiss will play France's Gael Monfils in Friday's second singles tie as Switzerland travel to Lille.
Last Sunday the 17-time Grand Slam champion withdrew from the ATP World Tour final against Novak Djokovic because of his back problem.
Federer, 33, is joined in the Swiss team by Stan Wawrinka despite their row at the London tournament.
Federer subsequently played down the argument, describing it as "heat of the moment" and insisting the pair "are friends, not enemies".
He told reporters on Thursday: "I'm just pleased that I can play tomorrow, give it a go. Things have been going well."
His match against world number 19 Gael Monfils is second on the bill, with world number four Wawrinka facing France's world number 12 Jo-Wilfried Tsonga in the opening tie in northern France.
Marco Chiudinelli and Michael Lammer will be the Swiss pair in Saturday's doubles against Julien Benneteau and Richard Gasquet.
Federer will then face Tsonga in the reverse singles on Sunday with Wawrinka playing Monfils in the potentially decisive fifth match.
Davis Cup final schedule
Friday (play starts at 1300 GMT):
Jo-Wilfried Tsonga (France) v Stan Wawrinka (Switzerland)
Gael Monfils (France) v Roger Federer (Switzerland)
Saturday (play starts at 1430 GMT):
Julien Benneteau/Richard Gasquet (France) v Marco Chiudinelli/Michael Lammer (Switzerland)
Sunday (play starts at 1200 GMT):
Tsonga v Federer
Monfils v Wawrinka