Sainz takes maiden pole for 150th start at British Grand Prix
The 27-year-old Spaniard clocked a best lap of one minute and 40.983 seconds to beat the Red Bull driver by 0.072 seconds in the closing minute of a tense session run in treacherous wet conditions.
His first pole came ahead of what will be his 150th Grand Prix start in Sunday's race, just two weeks after he was a very close second to the Dutchman in a thrilling finish at the Canadian Grand Prix.
In a topsy-turvy session that saw positions shuffled rapidly in the changing conditions, Charles Leclerc was third in the second Ferrari ahead of Sergio Perez of Red Bull and home hero seven-time champion Lewis Hamilton of Mercedes.
After promising to fight for the front row, it was a disappointment for the local fans as Hamilton failed to extend his run of eight British front row starts.
Lando Norris was sixth for McLaren ahead of two-time champion Fernando Alonso of Alpine, George Russell in the second Mercedes, Zhou Guanyu of Alfa Romeo and Williams' Nicholas Latifi.
"I put together a lap that I thought was nothing special, but it was on the board to see how it was -- and it was pole position which came as a bit of a surprise!" said Sainz.
"I was struggling a lot with the standing water. There was a lot more standing water on the racing line and it was very easy to have snaps and lose the lap."
He added, as a joke, that as a Spaniard he was unaccustomed to racing in the wet British conditions.
Verstappen, who was briefly booed by a section of the crowd, said: "It was tricky -- raining and drying, so you had to be on the track at the right time. The car was working well, but it was a bit of a lottery."
Leclerc, winner of six poles this year, said: "I'm happy for Carlos. He did a great job. I spun on the last lap, the lap when you need to put everything together -- and I didn't. So I didn't deserve to be on pole."
Wet and windy
The session began in wet and windy conditions with sufficient rain to persuade the teams to run on intermediate wet tyres, Leclerc swiftly setting the pace for Ferrari.
An early spin by Valtteri Bottas briefly brought out the yellow flags before the steady rain began to ease off and the circuit began to dry rapidly.
To the delight of the massed ranks of British fans, Russell was on top, before Verstappen emerged to demonstrate his current supremacy in all conditions.
The opening session ended with another nightmare for the Silverstone-based Aston Martin team, whose headquarters are within a short walk of the circuit.
Both four-time champion Sebastian Vettel, in 18th, and Lance Stroll, 20th, were eliminated along with the two Haas drivers Kevin Magnussen, 17th, and Mick Schumacher 19th, and 16th-placed Alex Albon in his heavily-revised Williams.
At the top, Verstappen led the way ahead of Leclerc and Russell.
The rain continued in Q2 with high plumes of spray making vision difficult as Hamilton struggled.
Briefly, Chinese driver Zhou went top for Alfa Romeo for a few early seconds before Alonso, Perez and the Red Bulls established the normal order and Hamilton slotted into second.
This left Nicholas Latifi clinging on in 10th place and a possible appearance in the top-ten shootout for Williams, equalling his previous best at last year's wet Belgian Grand Prix where he was classified ninth.
It was then Verstappen again ahead of Leclerc, Russell, Sainz and Hamilton, who was seeking to add to his haul of seven Silverstone poles and five in the last eight years.
As Q3 began, the rain eased with a warning that it would return, but the track remained slippery – proved when Verstappen spun and recovered on Hangar Straight, to gasps from the crowd.
With six minutes remaining, Alonso went top to be usurped swiftly by Leclerc and then Verstappen while Hamilton rose to second as the track began to dry with three minutes remaining.
It set up a thrilling finale as the drivers delayed to exploit the conditions with an 'as late-as-possible' lap – a scenario in which Sainz revelled with a pole-grabbing finale.