Serena Williams' achy left knee may not be the only barrier standing between her and an Australian Open title.

World No. 2 Simona Halep is already painting a mental picture of her and Williams in the finals of the first Grand Slam event in 2016, with the Romanian pulling off the upset for her first Grand Slam title, according to The Sydney Morning Herald.

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"I beat Serena once in my life, so it's really important for me," Halep, who has won just one of seven matches against Williams, said as she prepares for the Sydney International, the final tuneup before the Australian Open. "It's not easy to face Serena, of course. She's a big player, she's the best player in the world. But I have to believe, every time when I go against her on court, because when I played in Singapore, I have great memories from there

"When I went to the tournament, I felt I had everything to beat her. So if I believe this when I go against her on court, we'll be OK. But if not, I have no chance. To meet Serena, it means that I have to do finals. So let's go there in Melbourne to see if I can be there."

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Halep didn't just beat Williams in that 2014 WTA Finals round-robin match; she blistered Serena to the tune of 6-0, 6-2, handing the No. 1 player her worst loss on tour since she entered as a 16-year-old in 1998, USA Today Sports' For the Win reported.

Unfortunately for Halep, that tournament is not a single-elimination event, and the two eventually met again in the championship match. Serena exacted her revenge with a 6-3, 6-0 pounding of Halep.

And just like Williams, Halep is dealing with her own injury as the Australian Open approaches. Halep had to pull out of the Brisbane International with an Achilles injury that she says feels better but knows can flare up at any time.

Halep wouldn't face Williams at Melbourne unless both reached the finals. But under the tutelage of new coach (and former Andre Agassi mentor) Darren Cahill, she is exerting the power of positive thinking.

​"I think I have to be more confident in myself to believe that I can win it," Halep said. "If you believe that you can win it, you can do it. If not, it's more difficult.

"I feel that I'm ready. I have the game, I have the physical training every day good. I'm practicing well, I'm practicing hard. So we'll see. I know it's difficult. I know you have to be strong. I feel that I am, but still I have to go step by step."

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