Juan Martin del Potro admits he will have to play out of his skin to beat Roger Federer in the quarter-finals of the Australian Open and is looking for an improvement from the last time they met at the event (Del Potro 9/4, Federer 1/3 – Match Prices).

The 23-year-old reached the quarter-finals at Melbourne Park in 2009 but ran into an inspired Federer, who won in straight sets for the loss of just three games.

However, the Argentinian ace used that experience to embark on his best season as a professional, with a run to the semi-finals of the French Open before he claimed his first Grand Slam title with victory over the Swiss star at the US Open.

It was widely predicted that the South American would go on to become a multiple Grand Slam winner and turn the big four into a big five, but injury struck early in 2010 and he was forced to miss the majority of the year with a wrist problem.

There were signs of the old Del Potro in 2011 as he reached the fourth round at Wimbledon, but a third-round exit at Flushing Meadows proved that he still had some way to go to reach the heights of 2009.

But he has started 2012 in decent nick and moved into the last eight with a straight-sets win over German Philipp Kohlschreiber.

Del Potro knows he will be up against it on Tuesday but hopes to prove he is a better player than when he last faced Federer Down Under (Federer 13/8 – 3-0 – Set Betting).

“Roger is the best tennis player of the history, and of course he’s the favourite,” he said.

“I remember three years ago I played in the quarters against him and I only won three games. So if this time is something different and I win more games it is going to be OK for me.”