World championship leading teenager Kimi Antonelli continued his remarkable run of successes on Saturday by claiming pole position for Mercedes ahead of four-time champion Max Verstappen of Red Bull for Sunday's Monaco Grand Prix.
The 19-year-old Italian clocked one minute and 12.051 seconds to beat the Dutchman by 0.043 seconds in the final minute of a thrilling qualifying session that left both Ferraris on the second row of the grid.
After four wins, Antonelli will be seeking to become the first Italian to win five consecutive races since Alberto Ascari achieved the feat for Ferrari in 1952 after extending Mercedes' run to six successive poles this year.
Antonelli said he had produced "a magic lap".
"It was so close with Max!" he said after securing his fourth pole of the season.
Seven-time champion Lewis Hamilton was third ahead of Charles Leclerc, Isack Hadjar in the second Red Bull and Mercedes' George Russell, who is 43 points behind Antonelli in the drivers' title race.
McLaren's Oscar Piastri outpaced teammate and world champion Lando Norris to qualify seventh.
Antonelli's pole was the first by a Mercedes driver since Hamilton in 2019 and he became the first Italian to take pole in Monaco since Jarno Trulli in 2004.
The session began in warm sunshine with a long queue weaving out of the pits to warm their tyres in preparation for a flying lap, albeit in heavy traffic.
An early radio call from Hamilton to complain that Leclerc was "backing into me" reflected the tension in the cockpits before Hadjar vented his frustrations.
Leclerc topped the early runs ahead of Norris and Hamilton while Russell toiled for a clean lap before Gabriel Bortoleto clipped a barrier at the chicane and came to a halt, causing a six-minute red flag stoppage.
This left most drivers chasing a lap in the final seconds of Q1 while the main contenders stayed in the pits.
Leclerc led the way into Q2 ahead of Verstappen and Antonelli while a lap from Sainz, in the added time, saw him claim 10th and avoid an early exit.
ALONSO OUTBURST
Out instead went the two Cadillacs, both Haas drivers and both Aston Martins, with two-time champion Fernando Alonso, 21st, making clear his distaste for the new 'hybrid era' cars.
"The worst generation of cars I have driven in Monaco," he said.
"Hybrid cars should not be racing. Simple as that."
After 21 previous appearances, including two wins and two poles, Alonso, at 44, is the most experienced Monaco driver on the grid.
Verstappen led out for Q2, narrowly avoiding a pit-lane clash with Sainz before the precocious Antonelli set the pace in 1:12.778 ahead of Verstappen until Leclerc moved within 0.070 seconds of him.
It was tight and changeable at the top as Red Bull burst into the frame, Verstappen going fastest in 1:12.499 to beat Antonelli by 0.205 with Hadjar third 0.223 adrift ahead of the Ferraris and McLarens.
This time, both Williams and both Audis were eliminated, along with Alpine's Franco Colapinto Racing Bulls' rookie Arvid Lindblad.
Liam Lawson of Racing Bulls and Alpine's Pierre Gasly made the top ten shootout.
The final 10 had another chance to compose a perfect pole lap.
Leclerc bailed out of his first flying run, but hit the sweet spot on his second to clock 1:12.351 and snatch provisional pole.
In a sensational sequence, the celebrating Monegasque crowd were silenced as Verstappen clocked 1:12.094 before Antonelli blew that away as the tension erupted in Italian euphoria around the Monte Carlo harbour.