Roundup: Williams in, Djokovic out as Australian Open round two winds up

World No. 1 Andy Murray has some breathing space on the world rankings after defending Australian Open champion Novak Djokovic was sent home in a thrilling five sets.

Former world No. 33 Denis Istomin - who won the Asian wild card playoff to qualify for the Australian Open -- played the match of his life to defeat the Serbian world No. 2 7-6 (8), 5-7, 2-6, 7-6 (5), 6-4 in four hours, 50 minutes to the roar of an Australian crowd, a prospect that would have been "crazy" at the beginning of year.

"For me, (it) was impossible to think about that I can hold it five sets with Novak, physically and mentally," Istomin told reporters post-match.

"So I did well today."

Djokovic had his chances to take the match, however momentum shifted in the fourth set when opportunities slipped and Istomin on fire at the other end.

"No doubt, he was a better player in the clutch moments, he stepped it up, played aggressive, served very well, very precise, there's not much I could do," Djokovic said.

"Of course, I was not pleased with my performance overall, but I have to congratulate (Istomin) today."

It's Djokovic's worst performance at a major since a stunning stunning third round loss to Sam Querry at last year's Wimbledon, and a sour start to a grand slam career without longtime coach Boris Becker. The pair split at the end of the 2016 season.

But the women's draw is still looking tidy after U.S. powerhouse Serena Williams continued her Australian Open campaigned into round three, downing L. Safarova 6-3, 6-4 in an at times frustrating win.

Going up against a former top-10 player where the last time they met was a three setter at a Grand Slam final was not an "easy match" , Williams said in response to questions over the higher error rate than the Czech world no. 63, thus having to push harder to win the points.

"She's not someone you see in a second-round match," Williams said.

"I know that final was a tough three-set match, she never gives up... she's just always fighting to come back.

"So I knew that I wanted to jump out in the lead, I knew that I wanted to just be Serena. That's what I'm good at doing, is being Serena."

Rafael Nadal continued his comeback from injury, cruising past Marcos Baghdatis in a straight sets 6-3, 6-1, 6-3 win in the final match of round two.

Duan Ying-Ying will have to be at her very best on Friday when she takes on Venus Williams in the third round, China' s only singles player to remain in the Australian Open draw after a tough day for the ladies in round two on Wednesday.

Duan is clearly the rank underdog in her first ever third round in a major, though she has admittedly never seen the superstar play. Duan had a spirited 6-1, 3-6, 10-8 win against former world top 20 player Vavara Lepchenko. Endit