The five-time Australian Open champion was largely expected to wipe the floor with the 19-year-old American, and after winning the opening set appeared likely to do so.
But a beautiful display of power hitting gave Stephens the chance to fight her way back into the second set—hitting 11 winners in that set alone to force a decider.
The two women then traded service games in the third set before an incredible series of events took place in which Stephens ultimately prevailed.
Williams broke the service game of the youngster to lead 4-3 in the third set, but was then promptly broken herself to put the match back on serve. Stephens would then survive break points to take a 5-4 lead in the final set, and broke Williams to book her place in the final four of the tournament.
The American youngster was clearly overjoyed with the win, defeating one of the true greats of the modern game and an American legend at that.
Up until this match, Williams had conceded just eight games against her all tournament—leaving many to think that she would cruise to victory here.
Oh, how wrong we all were.
Serena Williams: has her 20-match win streak snapped with loss to Sloane Stephens— ESPN Stats & Info (@ESPNStatsInfo) January 23, 2013
Serena Williams had won her previous 13 matches in straight sets prior to her loss to Sloane Stephens— ESPN Stats & Info (@ESPNStatsInfo) January 23, 2013
Serena Williams was 39-1 since losing in the 1st round at 2012 French Open. She is now 39-2 after losing to teenager Sloane Stephens.— Numbers Never Lie (@ESPN_Numbers) January 23, 2013
The way she broke that racquet, Serena could have done the Psycho shower scene in one take.#hitchcock— Richard Hinds (@rdhinds) January 23, 2013
How do we know Sloane Stephens is 19? First thing she did after biggest win of her career was check her phone. #ausopen— Ben Rothenberg (@BenRothenberg) January 23, 2013
Stephens' victory was all set up by her power-hitting game—hitting 23 winners against a woman who usually dominates her opponents into submission.
But ultimately, the difference in the match would all come down to the ability to convert on break point—something Williams simply could not do.
The veteran finished with just four break points from her 12 opportunities whilst Stephens would take five from the eight chances she provided. Especially in the third set, with Williams up 15-40 and 30-40 a number of times, this would turn out to be her downfall—something she will rue throughout the remainder of the Grand Slam tournament.
Stephens now moves on to face world No. 1 Victoria Azarenka for a spot in the final in just her second appearance at the Australian Open.
As far as upsets go, there has been no bigger result and no more sensational occurrence than what just unfolded in front of us at Melbourne, Australia.
It seems as if America has a new hero—at least for tonight.
It's not the 15-time Grand Slam champion, Serena Williams.
It's the little-known 19-year-old Sloane Stephens who, with this result alone, has etched her name in tennis folklore for many years to come.
Is this the biggest upset of the 2013 Australian Open?
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