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Ivanovic knocks out Serena

AP, AFP-JIJI

Serena Williams’ long winning streak came to an end in a stunning fourth-round defeat to Ana Ivanovic at the Australian Open on Sunday.

Ivanovic hadn’t won a set in her four previous matches against Williams, who had been a hot favorite to win a sixth Australian Open crown for her 18th Grand Slam title. Williams later admitted she had been bothered by a back problem in practice in recent days and considered pulling out of the tournament.

The No. 14-seeded Ivanovic set up the 4-6, 6-3, 6-3 win by attacking the best serve in women’s tennis. She frequently stood well inside the baseline to receive, she took big swipes on her forehand and generally put Williams off her rhythm.

“It’s not easy playing such a champion . . . but she is also just a human,” said Ivanovic, who beat Venus Williams in the final of the WTA event at Auckland, New Zealand earlier this month. “I just went out there swinging at the ball.”

Williams hadn’t lost a match since August, one of only four defeats in 2013, and came into the fourth round with 25 straight wins. It was her 70th match at Melbourne Park, a record in the Open era, and she had already set the mark for most match wins ever at the Australian Open with her third-round victory.

“It wasn’t the best,” Williams said after being told her coach had released news of her back problem.

“Again, I don’t want to blame anything. I feel like Ana deserves all the credit,” Williams added. “I feel she played unbelievable today. I think she went for her shots. It’s not like I gave her the match.”

Williams has been almost perfect after winning the first set in Australian Open matches, losing only once in 52 previous matches after winning the opening set. That single previous defeat was against fellow American Sloane Stephens in the quarterfinals last year.

Ivanovic got on top early in the second set with some powerful forehand winners and never really let Williams back into the contest.

The 2008 French Open champion had 33 winners, including 20 on her forehand side.

Williams hit 22 winners but made 31 unforced errors, with most coming uncharacteristically on her backhand side.

“I made a tremendous amount of errors, shots . . . I haven’t missed since the ’80s,” Williams said.

Ivanovic advanced to a quarterfinal against the winner of Sunday’s later match between Australian wild-card entry Casey Dellacqua and No. 30-seeded Eugenie Bouchard of Canada.

The other quarterfinal on this half will feature two women who’ll turn 32 next month, with two-time finalist Li Na beating No. 22 Ekaterina Makarova 6-2, 6-0 and No. 28 Flavia Pennetta upsetting No. 9 Angelique Kerber 6-1, 4-6, 7-5.

In men’s action, top seed Novak Djokovic ensured there wouldn’t be consecutive upset losses when he beat Fabio Fognini 6-3, 6-0, 6-2 in a fourth-round match.

Immediately following fellow Serbian Ivanovic’s win over Williams, Djokovic raced to a 4-1 lead in the first set in just 19 minutes and won in 1 hour, 33 minutes to advance to the quarterfinals of his 19th consecutive Grand Slam.

It was also Djokovic’s 28th consecutive win dating back to his loss to Rafael Nadal in last September’s U.S. Open final.

Djokovic, who has captured six Grand Slam singles titles, next plays the winner of the match between Stanislas Wawrinka and Tommy Robredo later Sunday.

Third-seeded David Ferrer overcame a sluggish start to post a 6-7 (5-7), 7-5, 6-2, 6-1 win over Germany’s Florian Mayer and advance to the quarterfinals.

Ferrer was broken in the first game of the match and trailed 3-1 before taking control and triumphing in four sets.

Also Sunday, Tomas Berdych swept into the quarterfinals on the strength of his unbreakable serve.

The Czech seventh seed powered past seeded South African Kevin Anderson 6-2, 6-2, 6-3 in just under two hours to set up a quarterfinal with Ferrer.

Berdych maintained his impressive serving which, for the fourth match at the tournament, was not broken once — a run of 53 service games.

It is Berdych’s fourth straight quarterfinal at the Australian Open and it is the only Slam where he has yet to reach the semifinals. He trails Ferrer 4-7 in their meetings.

“I have a good memories from last season. We played twice, in Bercy and in London,” Berdych said.

“I beat him in London and the week before in Paris Bercy, I was very close. I lost to him in three sets. So I’m going to have a plan and I hope it’s going to be the right one.”