Australian Open: Serena Williams, Maria Sharapova and 'Black Heart' Rivalry

The bitter rivalry between Australian Open finalists Serena Williams and Maria Sharapova took root on the hallowed Wimbledon turf in 2004 and is still thriving more than a decade later -- both on and off the court. (It's Serena vs Sharapova in Australian Open final)

Sharapova was a 17-year-old unknown when she stunned the tennis world by winning at the All England club in 2004, going on to become a superstar with five Grand Slams who ranks as the world's highest paid female athlete.

The problem was, the fairytale victory that catapulted her to global celebrity came at the expense of Serena Williams -- top seed at the time and hot favourite for a third straight Wimbledon title -- a result that the American has never forgotten.

It has spurred her on to an overall record of 16-2 against Sharapova, with the Russian's last victory over the world number one coming more than a decade ago.

Since 2005, the American's winning streak is 15-0, including straight sets wins over Sharapova in the Australian and French Open finals (2007 and 2013), as well as the gold medal match at the 2012 London Olympics.

Williams could not resist a dig when asked this week about her last loss to Sharapova in Los Angeles 11 years ago, replying: "She was 17, super young and I think I was basically serving under hand."

The 33-year-old also spoke of the multiple major champion in terms more often used for promising rookies, saying: "She wants to improve her game, she wants to take it to the next level".

Sharapova admits her results against Williams are "terrible" and is desperate to break the sequence as their feud -- which at times has seen the pair trade personal barbs -- flares again on Saturday at Melbourne's Rod Laver Arena.

"I think my confidence should be pretty high going into a final of a Grand Slam no matter who I'm facing and whether I've had a terrible record, to say the least, against someone," she said.

"It doesn't matter. I got there for a reason. I belong in that spot. I will do everything I can to get the title."

- No cool parties -

Known for her steely composure on court, Sharapova admitted that Williams is one of the few players who riles her up.

"I think that's always made me a little bit too aggressive, maybe going for a little bit more than I had to," she said.

"She's great at making players hit that shot that you don't necessarily have to go for... it's been a really difficult match-up for me, but I'm a competitor. I'll go out and do everything I can to try to change that result around."

The animosity has occasionally spilled off-court, such as when Williams unloaded in a 2013 magazine interview about a top five player she didn't like.

"She begins every interview with 'I'm so happy. I'm so lucky' - it's so boring," she told Rolling Stone. "She's still not going to be invited to the cool parties. And, hey, if she wants to be with the guy with a black heart, go for it."

Everyone -- including Sharapova -- interpreted it as a reference to her relationship with Bulgarian player Grigor Dimitrov and the Russian fired back with her own pointed reference to Williams' and her French coach Patrick Mouratoglou.

"If Serena wants to talk about something personal, she should talk about her relationship and her boyfriend, who is married, who is getting a divorce and has kids, and not draw attention to other things," she said.

Williams declined to answer this week when asked if her head-to-head record with Sharapova was too one-sided to be considered a proper rivalry.

Sharapova knows that her status as one of the greats of the modern era will be questioned if she continues to be dominated by her biggest rival, whose 18 Grand Slams means her own place in the pantheon of tennis legends is assured.