Ferrari-backed Callum Ilott scored his maiden Formula 2 pole position for the Sauber Junior Team by Charouz.
Ilott, the only entry from the Sauber team following last weekend's tragic accident involving Anthoine Hubert and Ilott's team-mate Juan Manuel Correa, managed to master the wet conditions to beat his rivals by a narrow margin.
Virtuosi's Guanyu Zhou starts second, missing out on pole by just 0.143s, with ART's Nikita Mazepin making it an all-rookie top three.
The session was hit by rain showers throughout the session, which resulted in a very slippery track that saw a number of drivers running off or spinning.
The fastest laps came 10 minutes into the 30-minute session, which proved to be the driest period as the rain showers eased. Ilott used that break to take the top spot with a time of 1:33.887.
That was just moments before Carlin's Nobuharu Matsushita span at the Della Roggia chicane and beached his car in the gravel, triggering the first of two red flags.
The second came out for Arden's Tatiana Calderon, who spun at Ascari and hit the wall, stranding her. Marino Sato also spun as he returned to the pits under the red flag.
Championship rival Nyck de Vries will start fourth after improving late on, beating Sergio Sette Camara, whp starts 5th.
Matsushita starts sixth from Nicholas Latifi and Jordan King, who was the only other driver to make a late improvement, jumping from 11th to eighth.
Mick Schumacher and Louis Deletraz completed the top ten for Prema and Carlin respectively.