Surprise pole-sitter Kevin Magnussen pledged "maximum attack" as he aimed to "have some fun" in the Sao Paulo Grand Prix sprint race.
Haas driver Magnussen, who claimed a podium finish in his first Formula One race back in 2014, had never previously topped qualifying.
Yet he claimed a shock pole position on Friday, ahead of world champion Max Verstappen and Mercedes' George Russell, to ensure he will start Saturday's sprint race at the front of the grid.
Magnussen recorded a fastest lap of 1:11.674 before a combination of a rain shower and a red flag due to Russell spinning off ended the session.
"You're kidding, you're kidding, you're f****** kidding me! I've never, ever felt like this in my life," the Dane said on the team radio after being informed he was P1.
Magnussen, the first driver from Denmark to claim a pole in F1, had hardly composed himself by the time he was interviewed following the race.
"I don't know what to say," said the 30-year-old, who signed for Haas earlier this year after Nikita Mazepin had his contract terminated.
"The team put me out on the track at the exact right moment. We were the first out in the pit lane and did a pretty decent lap and we are on pole. It is incredible.
"Thank you to Gene Haas and [team manager] Guenther Steiner and the whole team for this opportunity.
"It has just been an amazing journey. It is incredible, thank you."
Asked about his plan for Saturday, Magnussen quipped: "Maximum attack, let's go for something funny."
Magnussen might still have his work cut out to hold off the Red Bull of Verstappen, who said: "We are still at the front. We just stayed calm from Q1 to Q2, then Q3 was where it was a bit more of a lottery but we are still on the front row."
Russell had to settle for P3 following his spin, though the Briton believes the sprint race provides Mercedes with a prime chance to beat Verstappen.
"Firstly, I'm happy to be P3 and congrats to Kevin," he said. "What an awesome job he did and Haas – they truly deserve it for all the efforts they have been putting in.
"P3 is not necessarily where we wanted to be but it's a very good place to be starting for tomorrow's sprint race.
"I think it is our best shot at finishing ahead of Max and Red Bull if there are some mixed conditions. I think we are ready for a good couple of races."
1. Kevin Magnussen (Haas) 1:11.674
2. Max Verstappen (Red Bull) +0.203
3. George Russell (Mercedes) +0.385
4. Lando Norris (McLaren) +0.589
5. Carlos Sainz (Ferrari) +0.683
6. Esteban Ocon (Alpine) +0.751
7. Fernando Alonso (Alpine) +0.830
8. Lewis Hamilton (Mercedes) +0.937
9. Sergio Perez (Red Bull) +3.927
10. Charles Leclerc (Ferrari)