Nadal wobbles before reaching Qatar quarters
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DOHA (Reuters) - World number one Rafa Nadal suffered a rare second-set meltdown before recovering to beat plucky Slovakian Lukas Lacko and join rival Roger Federer in the Qatar Open quarter-finals on Wednesday.
Nadal, who has been suffering from a fever this week, took the first set on a tiebreak after both men had traded breaks before collapsing in the second, where he won just 11 points.
It was the first time Nadal had lost a set 6-0 since February 2009 when he was beaten in the final of the World Indoor Tournament in Rotterdam by Britain's Andy Murray.
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The Spaniard recovered brightly at the start of the final set to race into a 4-0 lead but dropped his serve for a fifth time in the match before closing out a 7-6 0-6 6-3 victory.
"It was really, really difficult," said Nadal, who is seeded to meet Federer in the final and will play Latvian fifth seed Ernests Gulbis for a place in the last four.
"Lukas played a great match and if he plays at this level it is going to be difficult for everyone to beat him."
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It was a slightly easier evening for Federer, who overcame a break in the second set to take a 7-6 7-5 victory over Swiss compatriot Marco Chiudinelli.
"It was really difficult today, under the circumstances," said Federer, who closed out the match with a smash. "Playing such a good friend is so rare for me. I'm happy the match is in the past and I can look forward."
Federer, twice champion here, will face sixth seed Viktor Troicki in the last eight after the Serbian eased past Russian Teymuraz Gabashvili.
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Third seed Jo-Wilfried Tsonga of France, making his comeback from injury, moved into the quarter-finals with a 6-2 6-4 defeat of Ukraine's Sergei Bubka, son of the former Olympic pole vault champion of the same name, and will face Spanish seventh seed Guillermo Garcia-Lopez for a place in the last four.
(Reporting by Patrick Johnston in Doha and Martyn Herman in London; Editing by Clare Fallon)