The session featured two red flags, the first for a terrifying accident for Tsunoda, who lost control on the entry to the Villeneuve chicane and spun across the gravel before the car was launched into the air off the tyre barrier.
It somersaulted and landed upside down, before righting itself upon landing. The Japanese was uninjured and able to walk away from the crash.
Tsunoda was not the only driver to hit the barriers, as Alpine debutant Franco Colapinto also spun into the barriers, this time at the Tamburello chicane.
Colapinto’s was a less dramatic accident, as he lost control on the exit kerb and spun across the grass before going nose-first into the barrier. The Argentine was also unhurt.
The pole fight always looked to be between the McLarens and Verstappen, and the Red Bull driver laid down the gauntlet with the fastest time on the first runs in final qualifying.
Piastri ran first on the final runs, and was looking good after the first two sectors, only to come across a run of about five cars preparing their laps as he reached the two Rivazza left-handers that end the lap.
He could not improve his time in that sector of the lap but the first two sectors had been enough to vault him ahead of Verstappen.
The Dutchman did improve on his final lap, but only by 0.07secs and he just fell short of pole.
Norris, third fastest on his first run, was unable to improve and was leapfrogged by Russell, who used the medium tyres on his final lap, echoing the wider use of mediums by Aston Martin through the session.
Piastri said: “Very tough session with the red flags and also the tyres. Today the C6 (compound, the soft) was a real mystery.
“The team did a nice job getting the car into a good place. The last lap was good, I had about four cars in the last corner which didn’t help but it was enough.”
Verstappen said: “Everything was going really well, just the softest compound, it is very difficult to keep them alive around the lap. Sector one was good and then the tyres fell away from me. George set his time on a medium. The soft was maybe a bit too soft for this track.”
Norris said: “I guess I just wasn’t quick enough. None of my performances in Q3 have been strong enough this year, so same thing.”
Pirelli brought the three softest tyres of their range to this race in the hope of preventing the race being the locked-in one-stop strategy it has traditionally been at Imola.
That looks unlikely to work, with the medium compound working well, and Aston Martin leaned into it throughout qualifying.
The Aston Martin has a major upgrade on it this weekend, with a new floor and engine cover influenced by design legend Adrian Newey, who joined the team as managing technical partner in March.
Alonso and Stroll clearly had a strategy to use the mediums, as they turned to them for their final runs in each session.
Even though the team had no brand new mediums to use in the top 10 shootout, Alonso vaulted up from the seventh place he had secured with soft tyres on his first run to an excellent fifth on his second.
