Tenth seed Coco Vandeweghe voiced her frustration over a lack of bananas as she lost to Timea Babos in the Australian Open first round.

“I’m waiting for the bananas,” the American told chair umpire Fergus Murphy after the first set when asked why she was not ready to play.

“Why should I feel uncomfortable because the court is ill prepared?”

Vandeweghe became the third American seed in the women’s draw to fall on the opening day in Melbourne.

US Open champion Sloane Stephens was knocked out by China’s world number 34 Zhang Shuai, who came through 2-6 7-6 (7-2) 6-2 in one hour and 58 minutes.

The world number 13 served for the match at 5-4 in the second set, before Zhang, 28, recovered to win the tie-break and also take the final set.

It was an eighth loss in a row for Stephens, whose last win came in the US final at Flushing Meadows in September.

Meanwhile, Venus Williams – a finalist in Melbourne last year – lost 6-3 7-5 to world number 78 Belinda Bencic.

In total, 12 US players went out on day one of the tournament.

• Edmund beats Anderson in five sets
• Nadal impresses in first-round win
• Kyrgios powers into second round
• Live scores and results

‘It’s not my fault that this court is ill prepared’

Vandeweghe received a code violation after refusing to restart play at the end of the first set until bananas were delivered.

She was given a second code violation after later appearing to swear at her Hungarian opponent, who won 7-6 (7-4) 6-2.

A semi-finalist last year, Vandeweghe said she had been suffering with flu in the days leading up to her Grand Slam season opener on Hisense Arena.

She showed her frustrations in an animated exchange with the chair umpire about fruit not being available when she needed it.

“How are they not on court? I mean, that’s not my fault,” she exclaimed.

“Why do I have to play under a different set of rules? I have needs and it’s not my fault that this court is ill prepared.”

Vandeweghe was then docked a point for a comment made at Babos. The American said she was not happy about Babos getting “in her face” but the Hungarian denied trying to provoke her.

“She always does that [loses her temper],” Babos, the world number 51, said. “A couple of racquets are broken every match, this time it was I believe a time violation, but I’m not sure.

“The second one I believe was an insult against me. If the umpire heard it then it must have been this.”

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Nick Kyrgios made a confident start to his Australian Open campaign with victory over Brazil’s Rogerio Dutra Silva in 87 minutes.

The 22-year-old Australian, seeded 17th, raced to a 6-1 6-2 6-4 victory in round one.

Kyrgios won the warm-up tournament in Brisbane, raising Australian hopes of a first men’s singles champion in Melbourne since 1976.

He will face Serbia’s Viktor Troicki in the second round on Wednesday.

“I was very nervous coming out here, first match at the Australian Open,” Kyrgios said.

“I didn’t think I played as well as Brisbane but hopefully I continue to improve and find my feet out here.

“A couple of years ago I made the quarter-finals here and I’m just trying to emulate that and maybe go a little bit further.”

• Top seed Nadal cruises into second round
• Live scores, schedule and results
• BBC coverage times

There was an early warning for Kyrgios when umpire Fergus Murphy took exception to his admonishment of the crowd for calling out, and a debate ensued between the pair at the changeover.

However, Kyrgios remained focused where it mattered, dominating against world number 98 Dutra Silva on Hisense Arena.

Sixteen aces and no breaks of serve illustrated his strength in that department, but the Australian’s return was equally impressive.

Kyrgios got 76% of returns in play, breaking the Brazilian’s serve five times as the pressure told.

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Grigor Dimitrov reached the Australian Open second round with a straight-set win over Austrian Dennis Novak.

Dimitrov, 26, won 6-3 6-2 6-2 in one hour 38 minutes on Rod Laver Arena.

“I just tried to be compact, focused, used every opportunity I had and tried to save some energy,” said the Bulgarian, a semi-finalist last year.

Eighth seed Jack Sock lost 6-1 7-6 (7-4) 5-7 6-3 to Yuichi Sugita as 10 of 12 Americans lost in the men’s and women’s singles on day one in Melbourne.

John Isner, the 16th seed, was among the casualties, going down 6-4 3-6 6-3 6-3 to Australia’s Matthew Ebden.

Canadian 18-year-old Denis Shapovalov reached the second round, seeing off Greece’s Stefanos Tsitsipas 6-1 6-3 7-6 (7-5).

Russian Andrey Rublev, 20, outlasted Spanish veteran David Ferrer to win 7-5 6-7 (8-10) 6-2 6-7 (8-10) 6-2, while Croatia’s sixth seed Marin Cilic beat Canadian qualifier Vasek Pospisil 6-2 6-2 4-6 7-6 (7-5).

• Live scores and results
• Edmund beats Anderson in five sets
• Williams knocked out by Bencic
• Stephens loses to Zhang

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Kyle Edmund claimed the best win of his career as he knocked out 11th seed Kevin Anderson in five sets at the Australian Open.

Edmund, the only British man in the singles draw, won 6-7 (4-7) 6-3 3-6 6-3 6-4 in the first round in Melbourne.

The 23-year-old, ranked 49th, twice came back from a set down and recovered from 2-0 behind in the final set to win in a minute short of four hours.

He goes on to face Uzbekistan’s Denis Istomin in the second round.

• BBC coverage times
• Live scores and results

Edmund had lost his only previous encounter with Anderson over five sets at last year’s French Open, and he was in no mood to suffer a similar defeat.

US Open finalist Anderson, 31, was predictably dominant for periods on serve, using his 6ft 8in frame to good effect as he finished with 35 aces to Edmund’s 11.

Edmund had been working on his returns in the off-season, however, and it paid off.

After losing a tight first set on the tie-break, Edmund’s heavy forehand began to find its range as he broke for 4-2 on his way to taking the second.

Anderson’s experience told in the third set as he reeled off six of seven points following a rain delay to move ahead once again.

However, urged on by a large British contingent on court three, Edmund broke early in the fourth and roared as he held on from 0-40 to consolidate.

Memories of Paris stirred when Anderson took control of the fifth set at 2-0, but this time Edmund hit straight back.

A shoulder rub was required as the match clock approached four hours but Edmund continued to play aggressively, forcing the errors from Anderson to break serve for a fourth time.

The Briton admitted before the match that he had lost too many matches from wining positions last year and he made no mistake this time, sweeping his 31st forehand winner of the day to clinch victory.

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