Sergio Perez on pole in Miami after Charles Leclerc brings out red flags with crash
Fernando Alonso (41) put his Aston Martin on the front row while double world champion Max Verstappen (25), who leads teammate Perez by six points after four races, will line up ninth on Sunday after failing to set a timed lap in the final session.
"It has been my worst weekend up to qualifying," said Perez, who made his luck as well as receiving a hefty slice of good fortune.
"We put in the lap when it mattered."
Verstappen, who leads Perez by six points in the championship after four races, had failed to complete his first flying lap and had everything riding on a second that never happened.
Perez will go top of the championship if he can convert pole into his third win of the season and end double world champion Verstappen's almost year-long run at the top.
"I was trying to put it on the limit and then I made a mistake and had to abort the lap," said Verstappen, who had been consistently faster than Perez in practice.
"Then you rely on a bit of luck that there is not going to be a red flag but that can happen on a street circuit. I'm just a bit upset with myself."
Kevin Magnussen (30) qualified an astonishing fourth for Haas.
Alpine's Pierre Gasly (27) will line up fifth with George Russell (25) in sixth place on the grid for Mercedes and Leclerc seventh despite the crash.
Verstappen will also have to get past Alpine's Esteban Ocon (26) in eighth place.
Alonso's teammate Lance Stroll (24) provided the early surprise by failing to make it out of the first phase, the Canadian qualifying only 18th.
Mercedes' seven times world champion Lewis Hamilton (38) provided the next shock, with the most successful Formula One driver of all time only 13th in his worst ever qualifying at any circuit in the United States.
"Left that way too late guys," Hamilton observed over the radio.
Williams' Alex Albon (27) and Haas's Nico Hulkenberg (35) qualified higher than Hamilton in 11th and 12th respectively.
Hamilton had swerved to avoid going into the back of Magnussen's Haas in the opening session, hitting the wall and telling the team over the radio to check his car's front wing.
McLaren's Lando Norris (23) and Oscar Piastri (22) qualified 16th and 19th respectively.
"There was nothing that surprised us. We knew it would be difficult to get out of Q1 and it showed," said Norris.
Logan Sargeant (22), the only US driver in the race, will start last of all for Williams.