Roger Federer
Roger Federer shakes hands with Andreas Seppi after he lost their third round match of the 2015 Australian Open. [Getty]

The 2015 Australian Open saw its first upset in the men's singles as former World No 1 Roger Federer was knocked out after a third round defeat to Andreas Seppi at the Rod Laver Arena.

The Swiss tennis ace lost the opening two sets, with the tiebreaker deciding the outcome of the second set. However, the four-time Australian Open winner bounced back in the third set, only to lose the final set on another tiebreaker.

Seppi defeated Federer in a four-set thriller as the final score was 6-4, 7-6, 4-6, 7-6 in the Italian's favour. Federer's 55 unforced errors to his opponents 40 cost him the match resulting in his elimination from the first Grand Slam of the year.

Meanwhile, Andy Murray progressed to the next round of the tournament after an easy win over Joao Sousa at Hisense Arena earlier. The Scot defeated the Portuguese tennis star in straight sets 6-1, 6-1, 7-5.

Marcos Baghdatis, on the other hand, also saw his dream of winning the Australian Open end after his defeat to Grigor Dimitrov in a five-set exciting encounter. The final score was 4-6, 6-3, 3-6, 6-3, 6-3 as the Bulgarian came from behind twice to win the match.

With Murray and Dimitrov winning their respective third round matches, the duo will face each other in the fourth round of the Australian Open and the winner of the clash will make it to the last eight of the tournament.