Roger Federer is fit enough to play the Davis Cup final doubles with Stan Wawrinka against French pair Richard Gasquet and Julien Benneteau on Saturday.
France and Switzerland ended the first day at 1-1 after Wawrinka defeated Jo-Wilfried Tsonga and Federer lost in straight sets to Gael Monfils in the opening singles on Friday.
Switzerland’s Marco Chiudinelli and Michael Lammer were initially set to play but Swiss captain Severin Luthi changed his lineup at the last minute.
Federer, who is chasing his first Davis Cup title, is hampered by a back injury but said he expects to play better as the weekend progresses.
Federer and Wawrinka won gold at the 2008 Beijing Olympics but lost the last four Davis Cup matches they played together.
Stan Wawrinka gave Switzerland the perfect start to the Davis Cup against France on Friday by defeating French number one Jo-Wilfried Tsonga 6-1, 3-6, 6-3, 6-2.
Watched by an all-time Davis Cup record crowd of 27,432, crammed into one half of a roofed Lille football stadium, Tsonga looked and played tight from the start.
World No. 4 Wawrinka converted his third break point of the match to lead 3-1 with his superb one-handed backhand drive regularly leaving Tsonga for dead.
The Frenchman saved a break-point in the opening game of the second set with a big smash that appeared to loosen some of his nerves. A Wawrinka double fault in the fourth game gave Tsonga his first break of the match to lead 3-1.
He held onto to that lead to level the rubber and the two went head-to-head in a tightly contested third set.
The turning point came in the sixth game when Tsonga's big first serve deserted him and a sloppy forehand drive wide put Wawrinka 4-2 and eventually 5-2 ahead.
The fan support had been muted to that point, but Tsonga got them going as he saved two set points with a thumping forehand winner and a blistering ace.
Wawrinka was at 0-30 on his following serve, but worked his way out of that hole and took a two set to one lead after a long rally that tested both men.
Tsonga had his back to the wall and the tightness he had shown in the first set returned as he dropped serve to open the fourth set.
An inspired Wawrinka then grabbed a doubled break to lead 5-2.
The Swiss No. 2 made no mistake from there, closing out the rubber with a simple push volley at the net, Tsonga having been dragged hopelessly wide right of the court.
The Australian Open champion hit 61 winners to Tsonga’s 39.
France, which last triumphed in 2001, is looking to win the cup for the 10th time while Switzerland is seeking its maiden title.