US tops France, awaits Spain in Davis Cup semis

Isner broke for a 5-3 lead and, having taken Tsonga's serve, made a statement with his next service game: holding to love and clinching the set in 34 minutes with another ace that whistled past Tsonga.

Isner appeared more troubled by a wasp fluttering around his face midway through the second set, failing several times to flick and then swat it away with his racket.

The tiebreaker went with serve until Isner smacked a big forehand down the line that rocketed past Tsonga. He clinched the set with yet another ace, timed at nearly 141 mph.

But Tsonga had to wait until the 11th game to actually break. The Frenchman found his touch and hit a crosscourt forehand on the run to make it 15-40. The American forced deuce, but Tsonga's two-handed backhand pass gave him another chance to break. He took it, prompting a huge roar from the crowd.

Tsonga took the set, but Isner stayed calm and took the match.