MELBOURNE, Australia - Naomi Osaka's historic win over Petra Kvitova in the Australian Open final has drawn record numbers of TV viewers in Japan, the tournament has revealed.

The women's final was the most-watched TV programme in Japan during the Australian Open, and at its peak moment around 22.5m viewers tuned into local channel NHK to a match that saw Osaka crowned as the first Japanese champion in Melbourne - and the first Asian World No.1.

There was additional viewership on pay-TV broadcaster WOWOW, too, with Osaka and ATP compatriot Kei Nishikori's matches averaging between 2.5m and 6m viewers.

"The Australian Open has always been very popular in Japan," said Australian Open tournament director Craig Tiley.

"Naomi also has a huge fan base, as does Kei (Nishikori) and with only a two-hour time difference the Australian Open is Japan's 'home' Slam.

"Achieving a 20m viewership on TV for any programme, in this age of media disruption, is extraordinary and an indication of how passionate the fans are about their local heroes. To put it into further context, the women's final was watched by more than double the average numbers of Japan's most watched weekly programmes."