Australian Open Tennis / Tony Keen / 29 January 2010 / Leave a comment Bet Now View Market

The Swiss ace will move one step closer towards his fourth Australian Open title, says Tony Keen.

Roger Federer (SUI) vs. Jo-Wilfried Tsonga (FRA)

Roger Federer survived a major scare against Russian Nikolay Davydenko to book his 23rd straight grand slam semi-final appearance and his seventh at the Australian Open.

The world No.6 had a decidedly flat-looking Federer on the ropes early. He was up a set and held a 3-1 lead and three break points in the second set before the Swiss ace clicked into top gear and reeled off up to 13 consecutive games at one point, en-route to a 2-6 6-3 6-0 7-5 victory.

The world number one will now face Jo-Wilfried Tsonga who gained some revenge for his loss to Novak Djokovic in the 2008 decider, with a 6-7 (5-7) 1-6 6-3 6-1 win over the Serbian in the quarter-finals.

Federer and Tsonga have met on two previous occasions, with the 15-time grand slam winner prevailing in Madrid in 2008 before the 10th seed won in Montreal last year.

However, both of those contests were best-of-three set matches. As Davydenko will attest to, it's a lot easier to defeat FedEx in a best-of-three match than it is in a best-of-five set clash.

Tsonga will try and play aggressively from the outset, but there is a question mark over whether he can play at the same level for a sustained period as his last two matches have been five setters. Despite this, the Frenchman is capable of causing an upset as he boasts a number of weapons, including a powerful serve, strong forehand and good net game.

In the end, Federer's experience on the big stage and ability to make big shots at key moments will prove to be pivotal.

Back Federer to win in four sets as Tsonga has the game to pinch at least one set from the classy 28-year-old.