ROME : Czech Radek Stepanek stunned an out-of-sorts world number one Roger Federer 7-6, 7-6 on Friday to qualify for the semi-finals of the Rome Masters.

It was only Stepanek's second victory over the Fed-Express in six matches but he was in great form as he made the most of his opponent's erratic play.

It means that both top seeds are out of the tournament following Rafael Nadal's defeat to Juan Carlos Ferrero on Wednesday.

The first set went with serve and few break opportunities until the tie-break.

Federer got up a mini-break as Stepanek went long but the Czech soon levelled matters.

And he took the advantage with a sublime drop volley before serving out the set 7-4 in the breaker.

Any thoughts of an immediate Federer response were quashed in the second game of the second set as Stepanek broke the world number one.

He moved 40-15 ahead and then the Swiss master shanked a backhand wide to gift his opponent an important advantage.

Stepanek was in inspired form and giving Federer almost no opportunities to break his serve, regularly hitting the lines and serving brilliantly.

However at 4-2 he played his worst service game of the match. From 15-15 he netted one backhand then went long with another to give Federer a 40-15 lead.

He saved the first as Federer shanked another backhand wide but Stepanek crumbled on the next point, netting a seemingly simple backhand volley.

However Federer's backhand then deserted him in the next game and and two wild errors gifted the Czech player another break advantage and a 5-3 lead.

Serving for the match, though, Stepanek again showed nerves and three errors gave Federer a break chance that he took with a sortie to the net and clinical backhand volley.

Both held to set up the tie-break which Federer began with two stunning passing shots, one off each side, to gain the mini-break.

He pulled off a second after a marathon rally in which he produced a brilliant defensive lob that had Stepanek scampering back from his attacking position before later firing a backhand wide.

But despite leading 4-1, Federer was broken back twice for 5-5.

He saved one match point at 7-6 but was immediately broken again and with the next match point on the Czech's serve, Federer couldn't pull it out the bag and went down 9-7 in the second breaker.

- AFP /ls