Team GB's Lizzie Neave raised the prospect of a medal in the canoe slalom after she came second in her heat on Monday.
Faced with a world-class field, including last year's European champion Jana Dukatova and two-time Olympic gold medallist Stepanka Hilgertova, she raced through her second run in a time of 98.92 seconds.
That left her only 0.17 seconds off first place set by Spain's Maialen Chourraut and raised the prospect of a British medal when she returns for the semi-finals and final on Thursday.
Neave's form to date has not made her the obvious candidate for a medal.
She finished 10th in the European championships in the K1 earlier this year and 16th at the world cup meeting in Cardiff.
But the 25-year-old, from Stone in Staffordshire, has been able to practice on the £35 million purpose built course for the last 18 months.
Neave had all but qualified after finishing fourth in the first run. But instead of easing off in her second run, she went back to her room and watched a replay of her performance to iron out her mistakes.
She said: "I don't think it was unexpected. I knew that if I went out and put a good run down it would be right up there with the top girls.
"It was a good feeling knowing that I could do a better after looking at the video from the first run.
"Certainly there were time losses in my second run. If I go out and improve on that run and iron out any time losses, I would be happy with that.
"I know that if I perform at my best, I can compete for a medal so we will just have to wait and see."
Meanwhile, Ireland's Hannah Craig just finished within the cut-off after posting a second run of 108.99 seconds. That places her 14th, with only 15 canoeists going through.
In the two-man canoe, British pairing Etienne Stott and Tim Baillie finished fourth in their heats - one place ahead of Richard Hounslow and David Florence.
Baillie and Stott, both 31, posted a first round time of 100.44 seconds, enough to guarantee a place in the semi-final on Thursday.
Florence and Hounslow were left with all to do in their second run. With only 10 places for the semi-final, they were placed 11th as they waited to start their second run after being hit with six penalties first time round.
But Florence insisted he never doubted their ability to qualify. The 29-year-old from Aberdeen said: "We had a good plan of what we wanted to do and all we did was set about doing the best we could."
The heat was won in the end by the French pairing of Gauthier Klauss and Matthieu Peche, who completed the course in 96.98 seconds.
The three-time Olympic champions and overwhelming favourites Pavol and Peter Hochschorner from Slovakia managed second place.