John Isner's big serve and solid forehand proved too strong for Jo-Wilfried Tsonga on Sunday as Isner defeated the Frenchman 6-3, 7-6 (4), 5-7, 6-3 to put the United States into the Davis Cup semifinals for the first time since 2008.
Tsonga had chances but could break his serve only once as the Americans took an unassailable 3-1 lead in the series, setting up a match against Spain. Defending champion Spain defeated Austria 4-1.
France made the final score 3-2 when Gilles Simon defeated Ryan Harrison 6-2, 6-3 in a match rendered meaningless by Isner's victory.
Leading the Americans in the absence of ninth-ranked Mardy Fish, the 11th-ranked Isner played well.
''If I play like I have this weekend, I can beat a lot of people,'' Isner said, looking ahead to the contest against Spain. ''Beating Gilles (on Friday) and beating Jo are two very good wins. If I can keep this level up, I am going to be very hard to beat.''
In other quarterfinals, host Czech Republic topped Serbia 4-1 and Argentina beat Croatia 4-1. The semifinals are in September.
Tsonga struggled to stay with Isner until his late rally.
''I gave everything I could in the battle,'' Tsonga said. ''I didn't have much luck today and John took his chances. At 0-3 down in the fourth set, it became 'Mission Impossible.' ''
Isner built on the US team's momentum after a straight-set doubles win on Saturday. He didn't face a break point, while the pressure was clearly on the sixth-ranked Tsonga to even the score at the Monte Carlo Country club.
''You have to congratulate him. John Isner was huge today,'' France captain Guy Forget said. ''He played very well and he has a lot of talent. Jim Courier is a great leader, and he has a lot of class.''
The French fans got behind Tsonga early. But when he got to deuce on Isner's serve in the seventh game, the American's response was simple — two aces that Tsonga couldn't get near.
Tsonga trailed 15-40 in the next game, and Isner broke for a 5-3 lead when the Frenchman's big second serve was slightly too long.
Isner made a statement with his next service game by holding at love and clinching the set in 34 minutes with another ace that whistled past Tsonga before he could move.
He offered Isner a gift of a break point at the start of the second set, sending a routine smash into the net. He saved that break point with a strong forehand that Isner could only paddle back into the net.
In the next game, Tsonga's drop shot gave him his first chance of a service break. But, as he did all too often, Tsonga went for an extravagant forehand winner and the ball went out.
Tsonga's mixed performance featured some great touches around the net and poor serving. He even shouted out 'Ah, non!' (Oh, no!) after a double-fault in the fifth game.
Isner appeared more troubled by a wasp fluttering around his face midway through the second set, failing with several attempts to flick and then swatted it away with his racket.
The tiebreaker went with serve until Isner stepped forward and smacked a big forehand down the line that rocketed past Tsonga. He clinched the set with yet another ace at 140 miles per hour.
Tsonga finally began to make inroads on Isner's serve in the third set, pressuring him at 15-40 in the third game. But he had to wait until the 11th game to actually break him.
Tsonga found his touch, wrongfooting Isner with a sublime crosscourt forehand on the run to make it 15-40. The American forced a deuce, but his opponent kept coming at him and a wonderful two-handed backhand pass gave Tsonga another chance to break. This time he won it, prompting a huge roar from the crowd.
With the Frenchman serving for the set, Isner missed a great chance at 30-30 when he stretched for a volley at the net and it landed just wide. Tsonga clinched the set on his second serve when Isner's return landed out.
''At that point, it was anybody's game, but I just stayed there,'' Isner said. ''I played three of my best matches all year on clay. It's a surface I enjoy playing on and a surface I think I can do very well on.''
However, the home crowd's hopes of a revival evaporated when Isner broke early in the fourth set and held on for a 3-0 lead. He sealed victory with a volley at the net and turned to celebrate with Courier, before remembering to turn back and wait for Tsonga.
Forget and four-time Grand Slam champion Courier then hugged.
''We always got on well as players,'' Forget said.
