Mercedes Formula 1 junior driver George Russell beat two of his ART Grand Prix team-mates in a thrilling battle at Monza to win the only GP3 race of the weekend.
Renault F1 academy driver, and Russell's title rival, Jack Aitken finished second ahead of Anthoine Hubert.
Nirei Fukuzumi, who secured pole when the practice results were used to set the grid after qualifying was washed out, did not take part as a mechanical issue struck just as he was due to leave to pits to take the start.
When the lights went out in the delayed race - postponed from yesterday due to the delays caused by wet weather at Monza - Russell leapt off the line from a net pole and held the lead on the run to Turn 1.
He emerged still ahead as Aitken out-dragged Hubert on the approach to Curva Grande to take second, but the French driver retook the place under braking for the Roggia chicane.
The race was then suspended following a dramatic high-speed crash between Leonardo Pulcini and Alessio Lorandi, with former mounting the rear of the Jenzer Motorsport-run car as they crashed into the barriers at the exit of the Roggia.
The safety car was deployed and stayed out for eight laps as the medical car attended to Pulcini while he was extracted from his car.
When he was recovered, the race got underway and Russell maintained the lead.
But Hubert found a way by and moved into first around half distance before Russell retook the lead by using DRS to attack at Turn 1.
The race was then suspended again as Juan Manuel Correa smashed into the back of his Jenzer team-mate Arjun Maini under braking for the first chicane.
That led race control to deploy the virtual safety car and the ART cars circulated nose-to-tail as Correa's car was recovered.
The restarted occurred as the top three were going through the Parabolica, and Aitken jumped both of his team-mates as they ran three-wide down the main straight - Russell briefly dropping to third before fighting back past Hubert.
Aitken and Russell then engaged in a frantic scrap, with the latter finally getting back to first with a better run out of the Roggia after they had gone side-by-side through the Curva Grande and come close to contact at the following corner.
Russell began to edge away thereafter and his victory was secured when Niko Kari crashed running wide at the exit of Lesmo one and the race - already reduced to a timed event - ended behind the safety car.
Marcos Siebert finished fourth ahead of Ryan Tveter, who started 17th, Guliano Alesi and Tatiana Calderon.
Julien Falchero, Kevin Jorg and Bruno Baptista rounded out the top 10.
Maini was the other retirement as his damaged rear wing let go in the closing stages, and GP3 debutant Dan Ticktum was classified 13th after picking up a puncture in a clash with Dorian Boccolacci, who eventually came home 14th and last after getting front wing damage in the incident.
|1||George Russell||ART Grand Prix||21||44m15.898s|
|2||Jack Aitken||ART Grand Prix||21||1.526s|
|3||Anthoine Hubert||ART Grand Prix||21||2.361s|
|4||Marcos Siebert||Campos Racing||21||2.959s|
|8||Julien Falchero||Campos Racing||21||7.044s|
|11||Raoul Hyman||Campos Racing||21||9.567s|
|12||Steijn Schothorst||Arden International||21||9.645s|
|15||Niko Kari||Arden International||19||2 Laps|
|16||Arjun Maini||Jenzer Motorsport||18||3 Laps|
|-||Juan Manuel Correa||Jenzer Motorsport||12||Retirement|
|-||Nirei Fukuzumi||ART Grand Prix||0||Not started|
|-||Leonardo Pulcini||Arden International||0||Retirement|
|-||Alessio Lorandi||Jenzer Motorsport||0||Retirement|
|22||Juan Manuel Correa||0|