Stan Wawrinka survived a second-set wobble to beat Jo-Wilfried Tsonga 6-1 3-6 6-3 6-2 and give Switzerland a 1-0 lead over hosts France in the Davis Cup final on Friday.
World number four Wawrinka was more consistent than French number one Tsonga in front of a record 27,432 crowd at the Pierre Mauroy stadium.
World number two Roger Federer, who missed training early this week due to a back injury, takes on Gael Monfils in the second singles later on Friday.
The doubles will be played on Saturday and the reverse singles on Sunday.
France, who last triumphed in 2001, are looking to win the Davis Cup for the 10th time while Switzerland are seeking their maiden title.
Wawrinka breezed through the opening set, relying on his accurate one-handed backhand to unsettle Tsonga, who had trouble finding his range with his usually booming forehand.
The Swiss bagged eight points on his way to a double break, sealing the set when Tsonga sent a forehand long.
Tsonga held serve throughout and clinched the set with a service winner.
But he lost the momentum, conceding a break for 4-2 by spraying another forehand wide and Wawrinka sealed the set on his second opportunity with a crosscourt backhand winner.
Wawrinka piled on the pressure and a backhand volley earned him a break in the first game of the fourth set, which he firmed up with another break for 5-2 with a backhand winner.
The Australian Open champion, who hit 61 winners to Tsonga’s 39, wrapped it up on his first match point with a routine volley following yet another charge to the net.