Australian Open semi-finalists prove that age is just a number

On Wednesday both Serena Williams and Mirjana Lucic-Baroni advanced to the semi-finals (where they will meet each other) with victories over Johanna Konta and Karolina Pliskova respectively.

Williams is 35 while Lucic-Baroni turns 35 in March, so - as Williams pointed out - at least one played aged 34-years-old or over will be in the final.

They could well be joined by the 36-year-old Venus Williams, although that depends on her beating the in-form CoCo Vandeweghe (the exception to the rule, aged 25).

We're constantly being told that tennis is being taken over by a younger generation and while that is certainly true to an extent, the success of these players show how much experience and ability can count.

Furthermore, all three have been written off to varying degrees over the past five years or so and for Lucic-Baroni and Venus Williams in particular their achievements mark a redemption of sorts - just rewards for all the hard work they have put in.

For Serena this is no surprise. She's playing some scintillating tennis at the moment and she'll be aiming to hold all the Grand Slams, something that just eluded her in 2015. Were she to do that this year it would cap off an incredible year.

However for her sister Venus and Lucic-Baroni this came from nowhere. No-one expected either to make it this far and they've been able to do so mostly because of the work they've been putting in the build-up to this tournament. It's only the third semi-final Williams has made since 2010, while for Lucic-Baroni it's her first since 1999!

Her backstory is well documented and to get to where she is now after everything she's been through is incredible.

Roger Federer and Rafael Nadal have reached the semi-finals of the same Grand Slam for the first time since 2014 and what's crucial here is that both look in excellent form. The way the pair dealt with Kei Nishikori and Milos Raonic respectively was remarkable and they haven't looked this fluent for a while.

It's distinctly possible that we could have Nadal and Federer facing each other in the men's final and the Williams sister facing each other in the women's - what a spectacle that would be.