Australian teenager Ashleigh Barty is excited to be taking on world No.1 Serena Williams and believes she can pull off an enormous Australian Open upset.

Australian teenager Ashleigh Barty believes she can produce one of the greatest upsets in Australian Open history against world No.1 Serena Williams.

Many would have treated drawing the 17-time grand slam champion in the first round as a nightmare.

But 17-year-old world No.153 Barty can’t wait to step on to Rod Laver Arena on Monday night.

“You have to go out believing you can win the match, otherwise there’s no point walking out on the court really,” Barty told reporters at Melbourne Park on Saturday.

“I’m going to do all that I can to try to win it.”

Williams is the hot favourite to claim the Open title for a sixth time and join Chris Evert and Martina Navratilova on 18 majors, which would leave her trailing only Steffi Graf (22) in the professional era.

Barty is just beginning her first full year on the WTA tour and hasn’t played since injuring an adductor muscle in Brisbane in late December.

But the Australian says she is fully recovered and will relish the experience.

“Not every week do you get to go out and play against one of the greatest champions of all time. I’m really excited for the challenge,” she said.

Only once in the Open Era has the women’s top seed lost in the Australian Open first round, when Romanian Virginia Ruzici fell to Australian Mary Sawyer in 1979.

But Williams saw enough of the one match Barty played in the Brisbane International, when she upset world No.32 Daniela Hantuchova, to approach her with respect.

“She’s extremely talented,” Williams, who won the Brisbane title, said.

“She moves well, she plays well, she serves well, she has good returns.

“I saw her play a little bit at Brisbane.

“I was actually super impressed with her game.”

Williams, 32, missed the 2011 Australian Open through injury and was troubled by ankle injuries during the past two Opens, both won by Victoria Azarenka.

But this year, the American great said she will enter the tournament in excellent physical condition.

And she’s keen to join Navratilova and Evert on 18 majors.

“It would mean a lot to be on the same level as such great players,” she said.