NEW YORK (AP) Australian Open champion Stan Wawrinka got a walkover into the fourth round of the U.S. Open on Saturday when Blaz Kavcic pulled out due to an injured right foot just before their scheduled match.

The Slovenian said he had pain in the ball of his foot that neither trainers nor doctors could relieve.

''There was not even a one percent chance I could play. The pain was too great,'' said Kavcic, who eliminated Jeremy Chardy in straight sets in the second round Thursday.

The third-seeded Wawrinka, a semifinalist in last year's U.S. Open, next plays the winner of the match between Tommy Robredo and 19-year-old Nick Kyrgios.

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