Antonio Giovinazzi has moved into the lead of the GP2 Series standings with only three races of the season remaining after a timely fifth win of the season in Sepang coincided with a dismal afternoon for title rival Pierre Gasly.
With Gasly coming into the race armed with a ten point advantage over Prema team-mate Giovinazzi, the stage was set for a dice between the pair after they qualified on the front row.
However, Gasly's terrible getaway from pole position would set the tone for his day, his car struggling for grip from the off as he steadily slipped down the order and eventually finished outside the points in 11th place.
By contrast, Giovinazzi made the most of his opportunity to leapfrog Gasly, coming out top in a tight first corner tussle with Raffaele Marciello to lead throughout the first stint.
Even so, the Italian was made to work hard for victory when a later pit-stop than Sergey Sirotkin would see the Russian driver shake out just in front after the mandatory stops. However, while the ART driver would hold his rival at bay in the ensuing laps, his tyres would drop with four laps remaining and allow Giovinazzi a run on him into the first corner.
With the pair just avoiding contact as Sirotkin snapped with a lack of grip, Giovinazzi would nose ahead to take a lead he'd pull to six seconds to the chequered flag.
With Gasly only scoring four points for his pole position, Giovinazzi now holds an 11 point lead over the Frenchman with three races of the season remaining.
Sirotkin followed home second, with Norman Nato resisting a race-long challenge from Alex Lynn to pick up the final podium position. Jordan King completed the top five ahead of Marciello. The initial leader ran third during the first stint only for a slow pit-stop to drop him out of podium contention.
Running a long first stint rewarded Luca Ghiotto and Mitch Evans with seventh and eighth, in turn earning them the front row for the sprint race. Pole position had looked set to go to Oliver Rowland, who battled for the podium at the one stage only for DRS and tyre issues to drop him back to eighth, where he spun on the penultimate corner and finished 12th.
Gustav Malja and Sergio Canamasas completed the top ten for the points, ahead of the frustrated Gasly and Rowland.