Valtteri Bottas surprised Mercedes-GP teammate Lewis Hamilton by taking pole position for the Russian Grand Prix.
The Finn claimed his second pole of the season, and first since Austria, with a lap time of 1 minute, 31.387 seconds.
He had already out-paced world champion Hamilton with their first efforts in the final part of qualifying, and then lowered his best time even further on his second run.
Hamilton ran wide on his final effort to ensure he could not improve and he will start alongside his teammate, but behind him, on the grid when the race begins at 3.10pm UAE time.
The first win of Bottas's F1 career came in Russia last season, but he has not won this year.
Hamilton had the consolation of out-qualifying title rival Sebastian Vettel, who had to settle for third in his Ferrari ahead of teammate Kimi Raikkonen.
Hamilton leads Vettel by 40 points, with only five more races of the season remaining after Sunday's action in Sochi.
The Red Bull Racing cars of Max Verstappen and Daniel Ricciardo were quick in practice, but did not set a time after getting out of Q1 as they will start at the back due to grid penalties for engine changes.
Kevin Magnussen was best of the rest in his Haas, ahead of Esteban Ocon's Force India and Charles Leclerc's Sauber.
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