Renault development driver Artem Markelov thrust himself back into contention for the Formula 2 championship with a brilliant win in Monaco, as the title leaders hit trouble.
Markelov pulled off a near-repeat of his 2016 triumph in the Principality as he ran a long stint on Soft tyres to build a sizeable advantage, ensuring he emerged from his mandatory stop in the lead.
In a chaotic race, where the full race distance was only just squeezed in, Toro Rosso-affiliated Sean Gelael was second, while ex-F1 driver Roberto Merhi picked up third position.
Pole sitter Alexander Albon and front-row starter Nyck de Vries had scrapped for victory during the opening stint as they edged clear of Markelov, only for their prospects to be undone by a Safety Car period.
The Safety Car period was triggered when championship leader Lando Norris tipped Ralph Boschung into the wall at Anthony Noghes, for which the Carlin driver received a penalty.
Albon and de Vries both opted to stop but incredibly the pair collided at pit entry, with Albon tipped into a spin and the delayed de Vries sustaining damage that ultimately ended his race.
It left Markelov in the lead – but he had yet to stop, effectively turning the battle for victory into a straight fight between himself and Gelael.
Gelael started 12th but made gains on the opening lap and was the lead driver to have stopped prior to the Safety Car period, and held eighth position.
When the race was restarted Markelov put in a sequence of blisteringly quick laps on increasingly used Soft tyres and made his stop on lap 35 of 42.
Markelov emerged with a slender two-second advantage over Gelael but cruised clear across the remaining laps to chalk up his second victory of the campaign.
Merhi, who raced for Manor Marussia in the 2015 F1 season, adopted a similar approach to Gelael and claimed third spot, while Louis Deletraz was fourth.
Arjun Maini was second at the restart and mirrored Markelov’s strategy, but was unable to live with the pace of the Russian Time driver and slipped to fifth when he made his stop.
Norris, despite starting from the back row of the grid and sustaining a sanction for his clash with Boschung, displayed strong pace as he salvaged points in sixth position.
Jack Aitken was a low-key seventh while Antonio Fuoco sustained a drive through penalty for a start line clash that eliminated Luca Ghiotto but salvaged eighth, and pole for the Sprint Race.
Nicholas Latifi and Nirei Fukuzumi rounded out the top 10, the Honda-backed driver finishing half a second clear of Arden team-mate Maximilian Gunther.
Mercedes-backed George Russell, victorious in Barcelona, retired early on after he misjudged a move on Gunther into Rascasse and clouted the wall.
Sergio Sette Camara was a non-starter after being ruled out of action on medical grounds following the hand injury he sustained in a qualifying crash.
Formula 2’s Sprint Race is scheduled for 17:20 local time on Saturday
