Melbourne: Roger Federer, the world number one is through to his 11th consecutive grand slam semi final at the Australian Open in Melbourne. And this will be his chance to avenge a rare loss to Andy Roddick at an exhibition event earlier in the month because he will be playing against him for a place in the final. This was not a vintage performance from Roger Federer, here in the near court, and his count of unforced errors was higher than normal. The defending champion has not yet lost a set this entire tournament, but he came very close in the second set against 7th seed Tommy Robredo. Federer prevailed in the tiebreak to lead by two sets. Federer eventually won 6-3, 7-6, 7-5 and later went on to say that his service was broken only due to the windy conditions. But he will have to get past the wind for his next match, a semi-final showdown with 6th seed Andy Roddick. Gritty performance Mardy Fish was like a fish out of water in his quarterfinal match against Andy Roddick. Fish, in the far court, finally had to pay an enormous rent to the man who was once his landlord. The 6-2, 6-2, 6-2 win a good workout for Roddick's semi-final showdown with the FedEx. Meanwhile, Serena Williams came within two points of defeat in her quarterfinal match against a spirited Shahar Peer of Israel. The two-time champion was flat in the first set and Peer took advantage. However, seven-time Grand Slam champion Williams showed real grit and desire to break back and then clinched victory on her first match point, edging out an equally gritty Peer 3-6 6-2 8-6. Serena's semi-final opponent will be Nicola Vaidisova of the Czech Republic. The 10th seed overcame fellow countrywoman Lucie Safarova 6-1 6-4 in 71 minutes.