Del Potro lost only 11 points over nine games serving in a 7-5, 6-1 decision over Brian Baker. He won 80 percent of the points serving and 59 percent off Baker's serve in the second set.
No. 6-seeded Mikhail Youzhny was on the court less than an hour in a 6-3, 6-1 win over Matthew Ebden. He faced two break points among the mere seven points he dropped while serving.
Paire's win put him into the quarterfinals Friday and two-time defending champion and world No. 1 Roger Federer while del Potro draws Anderson in his quarterfinal. Also Friday, third-seeded Richard Gasquet faces Youzhny and Grigor Dimitrov goes against Mathieu.
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