Serena Williams and Maria Sharapova are scheduled to face each other at the 2014 Australian Open, leaving many fans wondering their feud over comments made about coach and rumored boyfriend Patrick Mouratoglou will resurface.

Sharapova did not take back comments she made about Serena Williams at Wimbledon in a New York Times article last month, giving the impression that the relationship between the pair was still cold, Sports Illustrated writes.

Although Serena Williams holds more widely-respected stats than Sharapova, the American tennis star showed frustration throughout the beginning of her first match at the Australian Open.

Despite winning the match, the 32-year-old American tennis star encountered her most glaring error in the sixth game of the second set when a looping backhand from Petkovic landed just over the net to set up an easy winner but Serena Williams was fooled by prodigious backspin and wildly missed the ball with a forehand, EuroSport.com reports.

Serena Williams' coach and rumored boyfriend Patrick Mouratoglou mentioned during a September interview that the American tennis star and Victoria Azarenka are "competing at the highest level," leaving many fans wondering if he predicted a rivalry during the Australian Open.

"Of course they have a good relationship, but it's difficult to have real friends," Mouratoglou said, according to ESPN.

"So, they're not real friends, but they appreciate each other, they're joking; they are friends, but as much as they can be because they're competing at the highest level."

Victoria Azarenka thinks her rivalry with Serena Williams is making her a better player and is looking forward to renewing it over the next four weeks at the Brisbane International and the Australian Open, DNAIndia.com writes.