Australia's world champion Casey Stoner overcame a slight fever and wet conditions on Saturday to take pole position in the Czech MotoGP.
The Ducati rider, last year's winner at Brno, completed the 5.4-km course in two minutes 11.657 seconds to claim the 16th pole position of his career and his sixth in a row.
Yamaha's Valentino Rossi of Italy, this season's points leader, was second, 1.189 seconds slower. American John Hopkins, the 2007 Czech runner-up, rounded out the front row on his Kawasaki, qualifying 1.302 seconds slower on his return from injury.
The wet Brno track caused problems for the racers for much of the day.
"Unfortunately halfway through the session this afternoon, when it started to rain a little heavier, the track became very, very difficult," Stoner said.
"There were a few patches there that were catching a lot of riders out. I went in to turn one twice and lost the front and had to pick it up. Luckily there weren't really any off-track excursions."
Stoner said he had been fighting off an illness that sapped his energy for the past few days.
"I was running out of energy (yesterday) very quickly. This morning I woke up and feel completely different (now). My head cold feels worse but in general my fitness and my energy feel a lot better."
Sunday's race is expected to be close with Stoner battling seven-times world champion Rossi, who leads the Australian by 25 points in the standings.
Hopkins could also mount a challenge after missing the past three races because of an injured knee, which he rested in the wet weather.
"Fortunately we were able to get a good lap in before the standing water had come in," the rider said. "Then we basically sat out the rest of the session because my knee has been sore. I'm still hoping for a dry race (tomorrow)."
Fifteen riders qualified for Sunday's race, the first since Rossi won the U.S. Grand Prix on July 20.
James Toseland of Britain crashed out midway through the session and failed to qualify on timings along with Jorge Lorenzo of Spain.
However, race organisers allowed the riders to compete on Sunday when they will line up in 16th and 17th position respectively.