Australian Open 2015: Venus and Serena Williams, Novak Djokovic and Stanislas Wawrinka in quarter-final action

Serena and Venus Williams could be in for an Australian Open semi-final showdown if they both manage to beat their younger rivals at the Rod Laver Arena.

The last time the two met in a Grand Slam was at the 2009 Wimbledon final.

Venus will face Madison Keys, who was not even born when Venus made her professional debut. The American teenager has cited the 34-year-old as her inspiration for becoming a professional tennis player and is now coached by Lindsay Davenport.

Keys will provide a challenge for Venus given her performance in the tournament so far, as the 19-year-old wasn’t intimidated by another Wimbledon champion, beating Petra Kivitova 6-4 7-5 in the third round.

Venus said of her young opponent: "Madison hits a clean ball, goes for it. Lindsay used to hit a clean ball. She was so fun to watch play. I loved watching her play. Of course, you didn't love watching her hit those clean balls against you. So it looks like it's a good match."

Serena may have an easier time against 11th seed Dominika Cibulkova of Slovakia who, like Keys, is yet to win a tournament on the Tour.

Cibulkova did, however, finish as a finalist in this tournament last year and beat two-time champion Victoria Azarenka in the last round.

The men's top seed Novak Djokovic will also be on court in the last match of the day against Canada's Milos Raonic.

Djokovic is yet to drop a set during the tournament and was unbeaten in all three of his meetings with the Canadian last year. However, Raonic has improved his fitness since then, with the Serb claiming that the eighth seed’s serve will be a concern.

Both players have hired former players to their coaching set-up to gain an edge, with Djokovic being guided by Boris Becker and Raonic by Ivan Ljubicic, the former world No 3.

Despite the partnership suffering a rocky start, Ljubicic said: "We had a difficult first few weeks because [Raonic] was struggling, out of confidence and out of shape, but we decided to try a little bit longer and the results started to come.

"[Milos is] one of the most determined and motivated people that I have ever met, and that meets my needs and my type of people that I want to work with."

It’s not just the top stars following the trend as last year’s champion and fourth seed Stan Wawrinka won his first major under former Swedish No 1 Magnus Norman. He will face fifth seed Kei Nishikori of Japan in the quarter-finals, who, incidentally, is coached by former French Open champion Michael Chang.

Chang, who helped Nishikori reach the 2013 US Open final and believes the ex-player coaches have caught on due to the perspective from their own careers, said: "The mentality and attitude ends up playing a very important role.

"We all know everybody can come out here and play great tennis, they all hit great forehands, great backhands and great serves, but the mindset is another element that the public and press don't see. I try to help him out and give him good advice wherever I can."