Serena Williams made a shock exit at the Australian Open as injury derailed her hopes against Sloane Stephens in the quarter-finals.

Not long after a courtside microphone picked up the comment during her quarterfinal with Sloane Stephens, 19, not only did she lose to the teen, but she received a code violation after smashing her racket in fury.

Sloane Stephens outplayed Serena Williams, whose movement and serves had been slowed by a back injury, and beat the 15-time Grand Slam champion 3-6, 7-5, 6-4.

It was Serena Williams’ first loss since August 17, and her first defeat at a Grand Slam tournament since last year’s French Open.

Serena Williams’ downer of a Grand Slam Down Under started badly when she turned her right ankle in her opening match at Melbourne Park.

“I’ve had a tough two weeks between the ankle … and my back, which started hurting,” Serena Williams said.

“A lot of stuff.”

While Serena Williams packed for home – she and sister Venus have also lost in doubles – Sloane Stephens advanced to a semifinal on Thursday against defending champion Victoria Azarenka.

Serena Williams hurt her back in the eighth game of the second set and things got progressively worse. She yelled at herself on several occasions, and smashed a racket into the court, earning a $1,500 fine from tournament officials.

“I was running to the net for a drop shot,” Serena Williams said, describing the lead up to her injury.

“As I went to hit it, it was on the backhand. I even screamed on the court. I totally locked up after that.”

She reiterated after the match that her injuries had made this Australian Open difficult for her.

“Absolutely, I’m almost relieved that it’s over because there’s only so much I felt I could do,” she said.

“I’ve been thrown a lot of (curve) balls these two weeks.”

Serena Williams smashes racket after losing Australian Open 2013 quarterfinal to Sloane Stephens

Sloane Stephens has been, too, but has coped well, and the magnitude of her accomplishment only hit her while she was warming down after the match.

“I was stretching, and I was like, <<I’m in the semis of a Grand Slam>>. I was like, <<Whoa. It wasn’t as hard as I thought>>,” she said.

“To be in the semis of a Grand Slam is definitely a good accomplishment. A lot of hard work.”

The No. 29-seeded Sloane Stephens hadn’t been given much of a chance of beating Serena Williams, who lost only four matches in 2012 and was in contention to regain the No. 1 ranking at the age of 31.

Serena Williams’ latest winning streak included a straight-set win over Sloane Stephens at the Brisbane International this month.

Sloane Stephens had a picture of Serena Williams on her bedroom wall growing up and she joked in the post-match interview: “I will have to put up a poster of myself now!”

Third seed Serena Williams looked set to make routine progress through to the last four when she led by a set and a break, but Sloane Stephens had other ideas.

Starting to display the kind of form which carried her to her maiden grand slam quarter-final, she was hitting freely from the back of the court and made several moves forward to finish points off at the net.

It was turning into a real contest between the experienced Serena Williams and the 19-year-old, understandably tipped as her heiress apparent in American tennis.

But then the match took another turn as Serena Williams sustained a back spasm in lunging for a low ball at the net.

The teenager broke for a 5-3 second-set lead and although she could not immediately serve it out, Serena Williams, after taking a medical time-out, bravely hitting back to level it at 5-5.

Sloane Stephens regrouped following a bout of jitters to break again and take it to a decider.

Serena Williams’ frustration boiled over after three games of the final set, earning herself a code violation for whacking her racket into the court.

But she could console herself with the fact her back appeared to be loosening up, perhaps as a result of the medication prescribed earlier starting to kick in.

Serena Williams broke for a 4-3 lead but Sloane Stephens was not going away and she hit straight back before edging 5-4 up.

And this time it was Serena Williams who buckled as a series of tired groundstrokes gifted Sloane Stephens the win of her life.

After the match Serena Williams indicated that she wasn’t entirely heartbroken by the loss.

“I’m almost relieved it’s over because there’s only so much I felt I could do,” she said.

“It has been difficult. I have been thrown a lot of balls this week.”

Sloane Stephens will now meet world No 1 Victoria Azarenka, who earlier beat Svetlana Kuznetsova 7-5, 6-1.
“It should be fun,” she said.

“I am in the semis of a grand slam so I will give it my all and do the same thing again.”

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