Slovak twins on course

The Hochschorners, the clear favourites, took first by a comfortable margin ahead of France's Cedric Forgit and Martin Braud, but were not happy with their performance.

"We're not very happy, we had errors, especially in the last upstream gate," Peter said. "Today was just training though."

The world number one duo does not expect an easier run in Thursday's final.

"There's no [such thing as] certain victory," Pavol said. "Tomorrow will be harder."

In the women's singles kayak event, Slovakia's Elena Kaliska, the defending champion, took top spot after compensating for a sluggish first attempt with the day's fastest run on her second try.

China's Li Jingjing, ranked 13th in the world, surprised the field with a second-place finish thanks to two consistent runs and world number one Stepanka Hilgertova of the Czech Republic, who is seeking a third Olympic gold after winning in 1996 and 2000, finished third.

Austria's Violetta Oblinger Peters, who only took up kayaking to keep an eye out for her younger brother, reached the finals.

Oblinger Peters went against the advice of her father, German white water canoe world champion Wolfgang Peters, in taking up the sport.

"My family really didn't want me to start kayaking," Oblinger Peters said. "They know it's a sport you have to be passionate about because you don't get any money, it's very expensive and it's very hard work for very little return.

"I started despite my father because my younger brother started and I had this feeling that I had to take care of him.

"And I'm very happy with the choice."

World number seven Oblinger Peters, who is married to four-time Olympian Helmut Oblinger, finished sixth in the preliminary runs to qualify for Thursday's finals.