Australian Open 2012 TV Schedule: The 2 Must-Watch Matches for Day 9

The Australian Open will move on to the quarterfinals on Day Nine, and these are the matches you need to watch.

With Rafael Nadal, Roger Federer and Caroline Wozniacki all in action, we look at which matches you need to watch.

As things get serious, there is a lot less action on the courts.  The action that is there is often special, though, so make sure you don't miss these matches on Day Nine.

Juan Martin Del Potro (11) vs. Roger Federer (3)

Roger Federer will face off against Juan Martin del Potro in the matchup of Day Nine.

Del Potro is still on his way back to the form that saw him win the 2009 US Open and has put in a strong showing so far in Australia.

But that is nowhere near as strong as the show Federer has given us.  The 16-time Slam champion looks to be in great form and will face a big test against del Potro.

Federer will come out victorious in this one, especially when you consider his easy passage so far.  A great match to watch, make sure you don't miss it.

Caroline Wozniacki (1) vs. Kim Clijsters (11)

World No. 1 seed Caroline Wozniacki faces Kim Clijsters in the top match of the women's draw on Day Nine.

Wozniacki is still chasing that first Grand Slam win and will need to get past Clijsters if she wants to keep hold of her No. 1 spot.

Clijsters will have other ideas.  Her dramatic comeback against Li Na in the fourth round showed she still has all of her heart despite knowing she is retiring later this year.

A tough one to call but I'll be expecting to see Clijsters progress from this after a close match.