Terrible day for defending champs as Ivanovic follows Nadal out of Paris

Defending champion Ana Ivanovic crashed out of the French Open at the fourth-round stage on a day Dinara Safina confirmed her status as the title favourite with another ruthless display.

Eighth seed Ivanovic, who beat Safina in last year's final, stumbled to a 6-2 6-3 defeat to Belarus' Victoria Azarenka hours after the top seed had dropped just one game in her comprehensive thrashing of French hope Aravane Rezai.

Ivanovic admitted she did not feel 100% as her title defence ended on Suzanne Lenglen court.

"I started really well and felt good in the beginning but after the first point of the fourth game, I just started feeling so dizzy and I completely lost my balance," said the Serbian.

"After that, it was really hard. I struggled with looking up. But she played well."

Ivanovic tipped Azarenka, the ninth seed, as a contender for the crown but it is hard to look further than Safina, who she will meet next.

Safina ruthless

The Russian has dropped just five games in her remorseless march to the quarter-finals and was again in imperious form in her 6-1 6-0 triumph over Rezai.

"I'm feeling very good right now," said the world number one, who swept to victory in less than an hour on Philippe Chatrier court.

"I'm trying to be very professional and not waste energy. I think this is something new to me - before I would maybe just go out there and play and waste my energy.