Argentine top seed Juan Martin del Potro progressed to the quarter-finals of the Delray Beach Open with a straight-sets win over Reilly Opelka.
The 30-year-old is making his first tournament appearance since he broke his kneecap at the Shanghai Masters back in October, but he showed little sign of being rusty after winning in just an hour and 13 minutes.
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The 2011 Delray Beach Open champion will now face American Mackenzie McDonald in the last eight, while fourth seed Steve Johnson advanced with a straight-sets victory over Italy’s Paolo Lorenzi.
Meanwhile, Britain’s Dan Evans takes on sixth seed Andreas Seppi of Italy as he looks to join Del Potro in the last eight. Second seed John Isner will take on France’s eighth seed Adrian Mannarino.