Tauson wins Auckland title after Osaka retires injured

She showed glimpses of just how devastating she can be in Auckland on Sunday and grabbed a double break against Tauson with powerful hitting on both flanks in the opening set, which she wrapped up 6-4, despite dropping serve late on.

But the 27-year-old from Japan had tears in her eyes as she received treatment on court before the start of the next set and then threw in the towel, sparking concern about her fitness for this month's Australian Open.

The Melbourne Park major, where Osaka has won two titles, runs from January 12-26.