ROGER FEDERER defeated Philipp Kohlschreiber for the 10th time to reach the U.S. Open last 16 as Canadian golden girl Eugenie Bouchard suffered a potentially tournament-ending head injury.

    Five-time champion and world No. 2 Federer claimed a 6-3, 6-4, 6-4 victory over his 29th-ranked German opponent.

    The 34-year-old Swiss star, hoping to become the oldest champion since Ken Rosewall in 1970, will next face U.S. 13th seed John Isner, who progressed after Czech opponent Jiri Vesely retired with a neck injury after dropping the first two sets.

    Bouchard, meanwhile, was facing a battle to make her scheduled last-16 clash with Italy’s Roberto Vinci after injuring her head in a freak fall in the women’s locker room Friday.

    The 21-year-old Canadian star withdrew from the women’s and mixed doubles tournament on medical advice.

    “The severity of the injury was and continues to be assessed by the on-site medical personnel at the U.S. Open,” said tournament director David Brewer.

    “No determination about competing in the singles competition has been made at this time. Bouchard will continue with medical evaluation and treatment for the remainder of the day.

    “An update on her condition will be provided later.”

    Federer has now reached the fourth round in New York for the 15th year as he looks to return to the final for the first time since 2009.(SD-Agencies)