Storm Hunter’s breakout - and lucrative - summer has come to an end with defeat in the Australian Open women’s doubles semi-finals at Melbourne Park.

Teaming up for the first time with accomplished Czech Katerina Siniakova, Hunter went down 7-5 1-6 6-3 to Belgian Elise Mertens and Taiwan’s Su-Wei Hsieh on Thursday.

The loss also ended, for the time being at least, Hunter’s two-month reign as the world’s top-ranked women’s doubles player.

Ironically, Mertens will assume that status when the new rankings are released on Monday.

Hunter and Mertens, who reached last year’s Wimbledon final together, parted ways after falling in the semi-finals of the 2023 season-ending champions event in Cancun.

That result was enough to catapult Hunter to the top of the rankings before the 29-year-old revealed Siniakova as her new partner last month.

Siniakova had completed a career grand slam with fellow Czech Barbora Krejcikova, as well as winning an Olympic gold medal as a pairing.

In a twist of fate, Siniakova and Hunter beat Krejcikova and German Laura Siegemund in the Open quarter-finals on Wednesday.

But now Mertens will dethrone Hunter from top spot courtesy of her victory over the new golden girl of Australian tennis on Thursday.

“I have no words to describe this match,” Mertens said after she and Hsieh - coached by former Australian Open tournament director Paul McNamee - battled back from 4-0 down to snatch the opening set on Margaret Court Arena.

A brilliant defensive half-volley from Hsieh off a Hunter backhand overhead secured a decisive service break in the eighth game of the final set.

“It was a very tough match but, I’m very happy with the way we played,” Mertens said.

“Su-Wei saved that point from 4-3 to 5-3, I don’t know what she was doing.

“It was over two hours. Recovery is the key for now. We’ll be back.”

Mertens and Hsieh will play either fourth seeds Gabriela Dabrowski of Canada and Kiwi Erin Routliffe or Ukraine’s Lyudmyla Kichenok and Latvian Jelena Ostapenko in the final.

Hunter will have to console herself with a $475,000 month-long pay day for her memorable summer campaign.

In addition to her run to the Open doubles semi-finals, she helped Australia reach the last four of the United Cup and was the last local standing in the women’s singles with a first-time charge to the third round at a grand slam.