Stephens losing run since winning last year's US Open continues while Jelena Ostapenko secures her place in second round
Australian Open Day 1: Venus Williams, Sloane Stephens and CoCo Vandeweghe sent packing
The stark contrast in form between last year's two first-time grand slam champions continued as Sloane Stephens was bundled out in the first round of the Australian Open, while Jelena Ostapenko stormed into Round 2 on Monday.
American Stephens enjoyed a fairy-tale run to win the US Open last year ranked 83rd in the world but has not won a match since - a run that continued with a 2-6, 7-6, 6-2 defeat by China's Zhang Shuai on Margaret Court Arena.
Not that the 24-year-old American was getting too down on herself.
"Even though I lost, I'm not too sad. Everything is good. Relax, everybody. It will be OK. Don't worry. We will get back to having fun soon," she told reporters.
"Just give me a little bit to regroup and we will be OK."
Unlike Stephens the 20-year-old Ostapenko, who blazed to the French Open title last June to become Latvia's first grand slam champion, has suffered no such hangover.
She backed up her Paris exploits to reach the Wimbledon quarter-finals and third round in New York, and looked every inch a title contender in a 6-1, 6-4 defeat of veteran Francesca Schiavone to open proceedings on Rod Laver Arena.
Ostapenko, who had an edition of 55,000 stamps printed in her honour last year, all of which were sold in a day, trailed in the second set against the 37-year-old Italian 2010 French Open champion, but clicked into gear to move through.
The seventh seed had lost in the first round of both her tournaments so far this year, but back on one of the sport's grandest stages, she shone.
"I really enjoy to play on all centre courts, especially when there is a lot of people watching and supporting me, I really love that feeling," Ostapenko, who reached the third round here last year, told reporters.
"Of course it's tough, especially after winning at the age of 20. Everybody wants to beat you," she said. "But on the other side, I have nothing to lose. I already won the grand slam. I just enjoy every match and show my best."
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Stephens, 24, lacks the firepower of Ostapenko and while her defeat by Zhang was classified as a first-day surprise, it was quite predictable against an accurate opponent who just missed out on a seeding.
Stephens was assured in winning the first set and battled back from a break down in the second and served for the match at 5-4, only to be broken and dragged into a tiebreak.
Zhang, who reached the quarter-finals in 2016 as a qualifier, dominated the decider with her pinpoint groundstrokes to send the 13th seed spinning out.
Stephens was phlegmatic afterwards, laughing off questions about her loss of form.
"I wouldn't call them tough times. Everyone is so depressed and so down," she said. "I will have the best Instagram picture when I finally snap this losing streak.
"Tennis is definitely a roller-coaster. But I have learned to just not panic."
World No 5 five Venus Williams was another high-profile casualty.
Williams, who lost in the final to sister Serena last year, was stunned by Switzerland's Belinda Bencic, fresh from winning the Hopman Cup with Roger Federer.
The seven-time grand slam winner, in her 77th major, struggled against a player who had never before beaten her to go down 6-3, 7-5 and deprive the tournament of one of its biggest names.
It is the first time since 1997 that there will be neither of the Williams sisters in the second round, with Serena not playing after giving birth to her first child.
"I would like to have played someone easier," Bencic said.
"When I was a little girl watching on TV I would never imagine I would play them [the Williams sisters]."
Tenth seed and last year's semi-finalist CoCo Vandeweghe was sent packing from the Australian Open in the first round Monday on a horror day for American women.
Vendeweghe, who also made the last four at the US Open in 2017, was knocked out by Hungary's Timea Babos 7-6, 6-2.
She was the third American big name to fall on day one of the year's opening grand slam after Williams and Stephens.
Hungarian world No 51 Babos took just an hour an 46 minutes to oust a tetchy Vandeweghe, who complained to the umpire after dropping the first set about a lack of bananas on the Hisense Arena court.
Coached by former Wimbledon champion Pat Cash, the American committed 28 unforced errors.