American John Isner completed the elimination of Spain's top four seeds from the Heineken Tennis Open with a 7-6 (5), 3-6, 6-4 quarterfinal win over top-seeded Tommy Robredo on Thursday.
Spain supplied five of the eight seeded players for the tournament but only eighth-seeded Albert Montanes, who beat Swiss qualifier Michael Lammer 6-3, 6-3, made it past the quarterfinals.
Second seeded David Ferrer and fourth seeded Nicolas Almagro were beaten in Wednesday's second round while third-seeded Juan Carlos Ferrero was forced to retire in the second round with an ankle injury.
Robredo appeared on course for the semifinals when he led 3-1 in the deciding set but the big-hitting Isner clawed back a service break, then took the match with a second break in the 10th game.
Isner's win helped him improve on last year's quarterfinal exit in Auckland, when he reached the main draw through qualifying, and to avenge his narrow, three-set loss to Robredo while representing the United States at last week's Hopman Cup.
Robredo was unbeaten in singles as he led Spain to the Hopman Cup title in Perth, including wins over No. 4-ranked Andy Murray of Britain and Isner.
Robredo broke Isner's booming serve in the third game of the first set, but Isner recovered the break in the eighth and took the set into the tiebreak.
He trailed 1-3 in the tiebreaker but got even and served consecutive aces for a 5-4 lead. He took the set when Robredo narrowly missed a forehand pass at 7-5.
Isner saved four break points in his first service game of the second set but double-faulted on break point in the eighth game, allowing Robredo to serve out the set in 40 minutes.
Robredo broke Isner again to open the deciding set and seemed in charge at 3-1, but the American broke back and then held for 4-3, clinching the game with a second serve ace, his 19th of the match.
Robredo then saved four break points after trailing 0-40 in the eighth game, surviving the fourth with a net cord.
Isner held serve again then clinched the match with a service break.
``Golly, that was tough. It was back and forth the whole match,'' Isner said.
``I kinda ran out of gas a bit in the second set and I was down a break in the third but I was able to claw back,'' Isner said.
"He got that net cord on my break point and then had a broken string on match point. What were the chances?''
Isner's semifinal opponent will be Montanes, who was efficient in beating Lammer in 1 hour, 15 minutes.
Montanes gained the only break of the first set in the sixth game for a 4-2 lead and broke Lammers in the first and last games of the second.
"I played a great match,'' Montanes said through a translator. "It was a close match. I had to fight very hard and run for every ball.''
Wild card Arnaud Clement, whose second round ended near midnight Wednesday, returned to center court hours later to beat sixth-seeded Jurgen Melzer 6-2, 7-5.
His semifinal opponent will be fifth-seeded and former champion Philipp Kohschreiber, who beat Marc Gicquel of France 6-3, 6-1.
