World number one men's tennis player Roger Federer has been nearly unbeatable in the past year. But his warmup for the Australian Open has abruptly ended with a rare loss.

The Swiss star was upset Wednesday by German Tommy Haas in the opening match of the Kooyong Classic in Melbourne. Because he was playing in exhibition tournament, the loss will not count on his Association of Tennis Professionals Tour record.

The 41st ranked Haas fended off three break points while serving for the match and closed a 3-6, 6-4, 6-4 win with an ace. Federer said he is completely healthy and has no concerns that the ankle problem that curtailed his last season would flare up before the Australian Open, which starts Monday.

Some information for this report was provided by AFP and AP.