Lewis Hamilton was shocked to claim his first Formula One pole position in four races as both Red Bull drivers rued missing out by the narrowest of margins.
Mercedes driver Hamilton took pole in qualifying for the Emilia Romagna Grand Prix by just 0.035 seconds over Sergio Perez, with Max Verstappen just 0.087s back in third.
Charles Leclerc was fourth for Ferrari at Imola, with Hamilton's team-mate Valtteri Bottas struggling to eighth place.
That may give Red Bull a strategic advantage for the race, especially with their cars on split strategies as Perez will start on soft tyres while Hamilton and Verstappen will be on mediums.
Still, Hamilton was thrilled to emerge on pole, which came as a surprise to him after Red Bull's pace this weekend and the fact he did not improve on his first flying lap on Q3.
"It has been great," said Hamilton, who impressively won the first race of 2021 in Bahrain despite Red Bull appearing to have a pace advantage.
"I definitely didn't expect us to be ahead of two Red Bulls.
"They have been so quick this weekend, six tenths ahead at times, but the car was already feeling better from the beginning this weekend.
"Respect to the team for their hard work to narrow down the window [to Red Bull].
"I'm so happy because the first lap was really nice, really clean. The second had some improvements but overall wasn't as good as the first.
"I came around the last corner and heard that I got the pole and was super grateful."
The first qualifying session was halted with a red flag after a crash for Yuki Tsunoda, a session Bottas topped as both Williams cars progressed.
Perez – on his soft tyres – emerged at the top of the timesheets in a Q2 session that saw Carlos Sainz, Sebastian Vettel and Fernando Alonso among the eliminated drivers.
A dramatic Q3 then saw Hamilton just hold on to his lead set after the first runs.
Lando Norris thought he had put his McLaren on the front row, only to discover he had exceeded track limits, meaning he settled for seventh behind Pierre Gasly and team-mate Daniel Ricciardo.
Perez thanked his team after claiming second but felt he should have had pole.
The Mexican said: "Well done to the team. I made a mistake on Friday and made them the team work hard so it is a good recovery.
"The most important thing is we showed progress. I never expected to be here after where we were on Friday but we have been improving.
"It is P2, but I should've been on pole – I made a mistake on the final corner.
"Everything is positive and we have to make sure we keep progressing and Sunday is when it matters.
"Anything can happen – a different [tyre] strategy to Lewis and Max. It will be interesting to see what we can do. The important thing is we get those points and that learning which is the priority."
Verstappen had claimed the last pole of 2020 and the first pole of this season, while Bottas had started at the front in the penultimate race of last year.
World champion Hamilton ended his wait for pole here, but Verstappen is eager to make life difficult to him.
The Dutchman said: "Not so good in Q3. I went off at turn three, so a bit messy, just not a good lap.
"You can't be good every time, so we'll see what went wrong – but it was definitely not the easiest in Q3.
"It's still P3, which is a good starting position. It's going to be interesting. We have the two cars on the different tyres and we will try to make it difficult for them."
A 99th career pole position for Hamilton saw him make Imola the 30th circuit where he has topped the qualifying timesheet.
1. Lewis Hamilton (Mercedes) 1:14.411
2. Sergio Perez (Red Bull) +0.035s
3. Max Verstappen (Red Bull) +0.087s
4. Charles Leclerc (Ferrari) +0.329s
5. Pierre Gasly (AlphaTauri) +0.379s
6. Daniel Ricciardo (McLaren) +0.415s
7. Lando Norris (McLaren) +0.464s
8. Valtteri Bottas (Mercedes) +0.487s
9. Esteban Ocon (Alpine) +0.799s
10. Lance Stroll (Aston Martin) no time set