MIAMI • Top seed Stan Wawrinka crashed out of tennis' Miami Open on Tuesday, falling 4-6, 6-2, 6-1 to German young gun Alexander Zverev, who booked his first Masters 1000 quarter-final.
Roger Federer, Rafael Nadal and Kei Nishikori advanced to the quarter-finals on cue.
Wawrinka looked weary as he struggled through the third set of a match played on his 32nd birthday.
"I had one bad game to start the second set and then it was tough for me," Wawrinka, the reigning US Open champion, said.
"I don't know. I completely went down physically and mentally, and also my tennis was completely out. I had no more gas.
"For sure it's a disappointing match. I think the level was quite up and down. We were both fighting a little bit in the first set to find good level. It was really humid, not easy to play some great tennis."
Zverev saved four of five break points and won 75 per cent of his service points.
"I had to be aggressive. I felt like he was the one controlling all the points all the time, so I had to change that. It worked out well for me," the 19-year-old said.
The German, seeded 16th, will now face Australian Nick Kyrgios, who was impressive in a 7-6 (7-5), 6-3 win over Belgian David Goffin.
Federer had to work hard for his victory against 14th seed Roberto Bautista Agut, emerging with a 7-6 (7-5), 7-6 (7-4) win which set up a last-eight meeting with Tomas Berdych. The Czech 10th seed was a 6-3, 7-5 winner over France's Adrian Mannarino.
Nadal beat France's Nicolas Mahut 6-4, 7-6 (7-4) in a tightly fought contest and will face American Jack Sock, who comfortably beat his compatriot Jared Donaldson 6-2, 6-1.
Second seed Nishikori survived a scare against Argentinian Federico del Bonis en route to a 6-3, 4-6, 6-3 win. The Japanese, who lost to Novak Djokovic in last year's Miami final, will face Italian Fabio Fognini, who defeated American Donald Young 6-0, 6-4.
In the women's tournament, Czech second seed Karolina Pliskova avenged her Australian Open quarter-final loss to Mirjana Lucic-Baroni with a 6-3, 6-4 win over the 26th-seeded Croat to secure a spot in the semi-finals.
The 25-year-old will next face Danish 12th seed Caroline Wozniacki, who beat Czech Lucie Safarova 6-4, 6-3.
AGENCE FRANCE-PRESSE, REUTERS
ATP MIAMI MASTERS
Q-finals: StarHub Ch201, 9am
WTA MIAMI OPEN
Q-final: StarHub Ch203, 7am
