MELBOURNE (Reuters) - American Serena Williams has had more than her share of dramas at this year's Australia Open but the third seed is planning to be all business like in the second week at Melbourne Park.

Serena Williams of the U.S. hits a return to Ayumi Morita of Japan during their women's singles match at the Australian Open tennis tournament in Melbourne, January 19, 2013. REUTERS/David Gray

Williams, chasing her third straight singles grand slam title and 16th in all, rallied from 3-0 down in the second set to beat Japan's Ayumi Morita 6-1 6-3 in the third round on Saturday.

So far in the tournament, Williams has turned her right ankle and hit herself in the head with her racquet.

"That's it, I'm done, I'm done," Williams said, when asked if she had any more surprises in store. "That was it. Just wanted to do two things. Now I got it out of the way."

On Saturday, the only damage she did was to her opponent, especially on serve, as she slammed down one delivery clocked at 207 kilometres an hour (128.6 mph).

That is just short of the record of 129 mph held by her sister, Venus.

"I wasn't going for it that hard," Williams said. "Every time I go for it, to hit it really hard, it goes in the 190s. When I hit the 207, I was like, 'OK, the first one wasn't luck, maybe I can hit a 207'. So it was pretty cool."

Williams said the right ankle she turned in her first round match was improving little by little but she was more pleased with her calmness on court.

"I think it was 2011 when I first came back (after a year out with illness and injury) and I played the summer hard courts," she said.

"I started playing really well. For whatever reason, I just started getting really calm. I didn't grunt as loud. I wasn't making as much noise. I just became really calm."

The five-time Australian Open champion now plays Russia's Maria Kirilenko for a place in the quarter-finals and though she has won all their previous encounters, she said she would be taking nothing for granted.

"Maria is playing consistent tennis, especially the past 16, 18 months, she's been so consistent," Williams said.

"My goal is just to be really focused against such a player that's doing so well. She beat me at the (U.S.) Open in doubles (so) she's probably going to take that into consideration in the match."

(Editing by Patrick Johnston)

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