Novak Djokovic opens Australian Open defence with easy win

"Of course I support and I agree with his decision". People were calling me. "I'm glad he's thinking that way". It was just like, sometimes athletes just react.

"She's really young and really aggressive", Williams said.

Serena Williams hasn't played a sanctioned match since the US Open last September, which ended in her semifinal loss to Roberta Vinci which ended her bid for a Grand Slam - the sweep of all four major singles titles in a calendar year. "It was an hour and 43 minutes and I didn't feel it at all", Williams said. In this year's tournament, the Serb will be looking for a sixth straight Australian Open crown, but admitted his first round match-up against Chung will be tricky as the youngster from South Korea has nothing to lose in playing the "Djoker".

Williams had been dogged by lethargy in some of her early Grand Slam matches, but she showed none of that as she roared to a 4-1 lead as the temperature soared to more than 32C.

"I had an interrupted lead-up and lost some weight but I'm feeling much better now". "I'm happy to be back here". Williams said she felt good on the court after a lengthy layoff from tennis. And getting older isn't easy if you aren't a superhero, especially in tennis.

With Williams' knee giving her problems in the latter half of 2015 and in the lead-up to Melbourne Park, the Italian did her best to push her around the court but the top seed was moving freely and held for 1-1. Radwanska has been on a roll in recent months, winning the biggest title of her career at the season-ending WTA Finals in Singapore and then being crowned Shenzhen Open victor this month.

"You try to stay composed, not get carried away by heat or get distracted", Djokovic said. That means she likely also doesn't know that she could face former No. 1 and close friend Caroline Wozniacki in the fourth round and No. 5 Sharapova in the quarterfinals.

Nonetheless, she says the long break she took to rest and recover after the US Open helped her a lot.

But her serve, which produced nine aces and was broken just once, pleased her most.

"I have been going non-stop since the London Olympics and, seeing that this is another Olympic year, I kind of wanted to start the year out really fresh and really go at it again as hard as I can". "I'm here to focus on Australian Open".

Williams fought through many three-set matches in 2015 and while this one went only two sets, it was definitely a challenge. Down 5-1 in the third and final set, Williams seemed destined for defeat until she won six games in a row.

Asked how she rated her game, she credited her serve for seeing her home and gave herself an "A" for effort. "I think I served well today, " Williams said.

"I've been preparing well, taking some time to really work on certain things, get a good foundation, good base for the long season".

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