Pierre Gasly secured his third victory of the year, passing the race leader on lap four to claim the lead of the GP2 Series feature race at the Spa-Francorchamps circuit in Belgium.
Prema team-mate Antonio Giovinazzi bogged down from pole, which saw him drop down the field to eventually finish sixth, whilst a storming start from third gave Gustav Malja the lead from Gasly, Norman Nato and Jordan King.
It took Gasly a couple of laps to close up and get himself in a position to challenge Malja for the lead, which he eventually did on lap four as he mugged the Rapax driver at the end of the Kemmel straight.
Nato followed his countryman through one lap later and then King managed to get past during the pit stop to claim third.
When Gasly stopped, he remerged in P8, 18 seconds adrift of the leaders, who had yet to stop, but began his charge to reclaim the lead, starting with some brilliant overtakes to dispatch Daniël de Jong at Blanchimont, Mitch Evans at the bus stop and Jimmy Eriksson at Les Combes.
Nato handed second to King when his car died at the exit to the bus stop, prompting a VSC period and denying the Frenchman an almost certain podium finish.
Gasly easily contained the restart and eased away to an 11 second lead at the flag over King, with Lynn fighting his way up to P3 with a strong early stint after his stop.
Raffaele Marciello just held off his flying team-mate Artem Markelov for 4th, with Giovinazzi holding on for P6 despite racing with a broken front-wing.
Luca Ghiotto showed once again what he can do after claiming 7th from 14th on the grid, while Malja held on for Sunday's reverse pole as behind him Oliver Rowland and Sergio Canamasas collided on the final corner, handing P9 to a delighted Sirotkin.
Gasly eased away from Sirotkin in the drivers’ standings, 138 points to 115, ahead of Marciello on 114, Giovinazzi on 112, Rowland on 100 points and King on 98.