Stop-start rain and cool tyre temperatures led to a crash-strewn session that was finally abandoned with 40s remaining on the clock after Lando Norris hit the wall in Q3.
That prevented a final one-lap shootout for first on the grid for the Saturday sprint contest, which left Verstappen atop the times ahead of Leclerc, Norris and Kevin Magnussen.
On his second and crucial lap on intermediate tyres in Q3, despite a yellow flag for a stricken Valtteri Bottas, the Red Bull driver posted a 1m27.999s to move ahead of Leclerc.
The defending champion was quick to confirm he had lifted off and his lap time remained on the board despite the yellow, which soon developed into a red.
That move to back off proved critical when the session resumed only for Norris to crash in what had looked to be a three-minute final run to decide top spot.
Before anyone had set a time in Q3, had brought out a brief red flag after a wet-dry track caught the Haas driver out in the more treacherous second half of the lap.
He lost the rear of the car at the second entry of Acque Minerali and spun across the gravel but kept the rears spinning to eventually rejoin, but not before the session was halted.
Alonso was ready at the end of the pitlane when Q3 resumed after a five-minute delay, the Alpine driver then fighting the car and slithering off the road at Acque Minerali.
Perez and Verstappen aborted the second apex at Tamburello, the Red Bull duo both locking the front-left to run over the gravel as Leclerc set the initial pace with his 1m28.788s effort.
Verstappen soon crossed over the timing line just 0.02s adrift as he comfortably kept Norris at bay before running for another 1m27.999s flying lap that stormed to provisional pole.
The Red Bull driver was quick to confirm over team radio that he had still backed off considerably and changed down a gear to account for a yellow flag in the final sector.
That caution then morphed into another red flag in response to Valtteri Bottas parking up in his Alfa Romeo C42 on the downhill approach to Rivazza with a technical issue.
When the track reopened a quarter of an hour later for a final three-minute dash, the remaining eight drivers queued in the pitlane ahead of a one-lap shootout for pole.
But neither Verstappen nor Leclerc looked like improving when Norris binned his McLaren also at Acque Minerali, which settled the starting order and allowed Verstappen to land the first pole of his title defence as only one Ferrari driver was there to challenge him.
Fresh from signing a contract extension at Ferrari and in front of the team's home crowd, Carlos Sainz put his F1-75 into the wall on the exit of the penultimate Rivazza corner in Q2.
With the threat of rain returning, the first timed lap was predicted to be critical. Sainz flashed over the timing line in 1m18.990s and he had moved top ahead of Lando Norris.
Verstappen immediately improved and brought that benchmark time down to a 1m18.793s to nab first position as Sainz was told over team radio to push for a second flying effort.
But as he turned in to the second apex of the Rivazza left, the right-rear wheel appeared to run over the painted track border, and he span across the gravel and into the outside wall.
The front-left assembly bore the brunt, and the red flag was thrown before rain duly arrived.
After a nine-minute delay to retrieve the damaged Ferrari, conditions had deteriorated sufficiently to ensure no drivers rushed to return to the circuit with 11 minutes to run.
With the risk too great to attempt a lap on slicks, both Mercedes drivers were eliminated. George Russell, whose car had broken a floor stay in FP1 due to the extreme nature of the porpoising, missed the cut off on his only flying lap by almost six tenths to land only 11th.
He beat the Haas of Mick Schumacher while Lewis Hamilton failed to make Q3 for the second time in three races, the Briton having struggled to generate tyre temperature all day.
In 14th, Zhou Guanyu was another casualty of the declining conditions despite the Alfa Romeo driver having ended up fourth come the chequered flag of Q1 behind Sainz.
Lance Stroll rounded out the 15 and had vacated the car with three minutes to run, although teammate Vettel emerged from the pits a few second later along with Bottas, Alonso, Leclerc and Perez for Q3 sighters on intermediate tyres. None improved their time.
In the first part of qualifying, a downpour that persisted overnight on Thursday had all but stopped, with the support series creating a dry line to allow most drivers to begin on softs.
Alexander Albon caused a red flag only six minutes into Q1 as the Williams FW44 endured its latest brake failure, like that which hit Nicholas Latifi in Bahrain testing.
In the cool, damp conditions at Imola, Albon complained of losing his brake pedal altogether as he was captured crawling around with flames shooting out of the right-rear brake duct.
This was swiftly followed by a small explosion inside the assembly – likely to be the brake disc failing as it subsequently tore chunks out of the suspension to drop debris on track.
Albon had yet to set a time as Q1 was halted, while Lance Stroll led on a 1m23.419s to find 1.1s over fellow soft-tyre runner Valtteri Bottas and Max Verstappen on intermediates.
The 18-minute Q1 run was also a struggle on the other side of the Williams garage as Nicholas Latifi suffered a spin while accelerating on the exit of the Villeneuve chicane.
He locked the fronts to slow the car before he ran over the sodden grass, but as Latifi tried to return to the circuit, he lost the car again and spun to bring out temporary yellow flags.
Latifi eventually recovered to prevent a second stoppage, as Hamilton ran 1.6s adrift of the pace to just scrape into Q2 by only 0.004s while as per FP1, he struggled to heat the tyres.
That left Yuki Tsunoda to be the first driver to miss out on progressing into the second part of qualifying. Although, he did still find 0.25s over AlphaTauri stablemate Pierre Gasly.
Latifi ran to 18th fastest, while Esteban Ocon was hobbled for a significant portion by a gearshift issue to ensure his Alpine remained in the garage to only beat Albon for 19th.
| Cla | Driver | Chassis | Engine | Time | Gap | |
|---|---|---|---|---|---|---|
| 1 |  Max Verstappen |  | Red Bull | Red Bull | 1'27.999 | |
| 2 |  Charles Leclerc |  | Ferrari | Ferrari | 1'28.778 | 0.779 |
| 3 |  Lando Norris |  | McLaren | Mercedes | 1'29.131 | 1.132 |
| 4 |  Kevin Magnussen |  | Haas | Ferrari | 1'29.164 | 1.165 |
| 5 |  Fernando Alonso |  | Alpine | Renault | 1'29.202 | 1.203 |
| 6 |  Daniel Ricciardo |  | McLaren | Mercedes | 1'29.742 | 1.743 |
| 7 |  Sergio Perez |  | Red Bull | Red Bull | 1'29.808 | 1.809 |
| 8 |  Valtteri Bottas |  | Alfa Romeo | Ferrari | 1'30.439 | 2.440 |
| 9 |  Sebastian Vettel |  | Aston Martin | Mercedes | 1'31.062 | 3.063 |
| 10 | Carlos Sainz Jr. |  | Ferrari | Ferrari | ||
| 11 | George Russell |  | Mercedes | Mercedes | 1'20.757 | |
| 12 | Mick Schumacher |  | Haas | Ferrari | 1'20.916 | |
| 13 | Lewis Hamilton |  | Mercedes | Mercedes | 1'21.138 | |
| 14 |  Zhou Guanyu |  | Alfa Romeo | Ferrari | 1'21.434 | |
| 15 |  Lance Stroll |  | Aston Martin | Mercedes | 1'28.119 | 0.120 |
| 16 |  Yuki Tsunoda |  | AlphaTauri | Red Bull | 1'20.474 | |
| 17 |  Pierre Gasly |  | AlphaTauri | Red Bull | 1'20.732 | |
| 18 | Nicholas Latifi |  | Williams | Mercedes | 1'21.971 | |
| 19 | Esteban Ocon |  | Alpine | Renault | 1'22.338 | |
| 20 |  Alex Albon |  | Williams | Mercedes | ||
| View full results | ||||||
