U.S. Open champion Stephens a first-round casualty at the Australian Open

Sloane Stephens and her alarming form slump continued at Melbourne Park after the U.S. Open champion was bundled out of the Australian Open in the opening round.

Stephens claimed a maiden grand slam victory at Flushing Meadows last September but the struggling 24-year-old American is still searching for her first win since that triumphant display following Monday's shocking three-set loss to Zhang Shuai.

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The 13th seed was up a set and serving for the match at 5-4 in the second on Day 1 of the tournament before Chinese opponent Zhang rallied and completed a stunning 2-6, 7-6 (2), 6-2 victory in Margaret Court Arena.

Zhang, who contemplated retirement in 2015 before breaking through for her first slam win at the 2016 Australian Open after 14 attempts, broke twice in the final set as she closed out the first-round upset in just under two hours.

Heading into the opener, Pam Shriver described Stephens' slump from her U.S. Open triumph to being horribly out of form as "the most curious six months in the history of a professional tennis player."

Stephens made an astonishing recovery from injury to win her first grand slam title on home soil at Flushing Meadows last September, thrashing fellow American Madison Keys in the final. She surged more than 900 ranking places in the space of a month, coming from nowhere to be crowned champion in a story that even her most optimistic supporters could surely not have scripted.





But Stephens has experienced an alarming decline since her finest hour in New York, losing all eight of her matches after ruthlessly demolishing Keys.

Former world No. 3 Shriver is baffled by her compatriot's struggles, but thought the tide would turn ahead of her first-round match in Australia.

Shriver told Omnisport: "It's the most curious six months in the history of a professional tennis player. When you think not that long ago she was just coming back from almost a year out of the game, ranked 900 in the world.

"She lost to [Simona] Halep in [Washington] D.C. and then she went semifinal, semifinal in two big tournaments in Canada and Cincinnati and then she turned the tables at the U.S. Open.

"Physically and emotionally she handled the final so much better than Madison Keys, so much so that it wasn't even a contest in the end.

"But, if you look at her pattern, when she had her first grand slam breakthrough — sensationally beating Serena Williams at the Australian Open in 2013 and losing a really tough semi to Victoria Azarenka —- she then performed really poorly and started to get injured.

"You sort of think, well, the U.S. Open follows her pattern of when she does well in a major, gets distracted, struggles and for whatever reason she loses her way. Most people gain confidence when they do well in a major, but in this day and age in the women's game many have struggled after a breakthrough at a major.

"But this is an extreme, for Sloane to lose so many straight matches, it's really hard to imagine.

"Sloane obviously has such a difference between her high end, her fully confident self, and when she loses confidence, interest and struggles physically. She's too good lose that many games in a row. Obviously, it is life-changing to win a major. She had a big lie down and has not been able to get back up again, but she will be back."