But despite appearing to struggle with a back injury Murray, 20, won the final two sets to book a meeting with Ivo Karlovic in the next round.

Murray is drawn in the same quarter as world number one Roger Federer and in-form Andy Roddick.

The Scot is the only Briton in the singles, although his brother Jamie lines up alongside Max Mirnyi in the doubles.

Fellow Britons Alex Bogdanovic, Jamie Baker, Katie O'Brien and Anne Keothavong all lost in qualifying for the singles event.

Murray, a semi-finalist last year, is seeded to face Roddick in the fourth round before a possible quarter-final meeting with Federer.

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