United States' Serena Williams addresses a press conference following her semifinal loss to Japan's Naomi Osaka at the Australian Open tennis championship in Melbourne, Australia, Feb 18, 2021. (ROB PREZIOSO / TENNIS AUSTRALIA / AP)

MELBOURNE - Serena Williams broke down in tears before cutting short her post-match news conference after losing 6-3 6-4 to Naomi Osaka in the Australian Open semi-finals on Thursday.

The defeat ended Williams’ bid for a record-equalling 24th Grand Slam title.

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“It was a big error day for me today,” the 39-year-old told reporters after the match at Rod Laver Arena.

Asked if it was just a bad day at the office, Williams said: “I don’t know. I’m done,” before leaving the room in tears.