Andy Roddick's easy victory over fellow American Mardy Fish may be the last time he is relaxed- at least in the Australian Open this year. For looming in the semi-final is Swiss ace and Roddick's nemesis, Roger Federer. 

Roddick overcame Fish 6-2 6-2 6-2 in what was almost a walk in the park. However he is aware that he will have to be at the top of his game against the defending champion Federer. And Roddick was reminded of the ominous form that Federer is in as the Swiss giant demolished Tommy Robredo 6-3 7-6 7-5 even though he looked rusty.

"Conditions were very slow and it was windy so I had to adjust to that," Federer explained at a news conference. "Tommy is a tough baseliner so he plays it smart. I tried to change things up a bit but I struggled to find my rhythm. My attacking style worked out well and I volleyed really well. As long as I get through I'm happy."

Roddick was also pleased with his own form. "I think Mardy might have been a little bit nervous at the beginning as he made a few errors he wouldn't normally make but I was happy with the way I played," he said.

Elsewhere Serena Williams had to battle hard to overcome Shahar Peer 3-6 6-2 8-6. Williams now faces 10th seed Vaidisova in the semifinals. The latter overcame Lucie Safarova 6-1 6-4.