Bagnaia spent much of the 24-lap Spanish GP fighting with the KTM duo of long-time leader Brad Binder and Jack Miller and only moved into the lead on lap 21.
The Ducati rider kept a relentless Binder at bay to score his second grand prix win of the year to retake the lead in the standings after erstwhile championship leader Marco Bezzecchi crashed out.
Sprint race winner Binder and Miller completed the podium to cap off a banner weekend for KTM, while Quartararo was 10th after an eventful afternoon for the Yamaha rider.
The race was red-flagged on the opening lap when Quartararo and RNF Aprilia’s Miguel Oliveira tangled at Turn 2.
Quartararo made a solid launch from 16th on the grid but found himself hemmed in between Bezzecchi – who had a slide exiting Turn 1 – and Oliveira.
The Frenchman could do nothing to avoid contact with Oliveira, which took both riders down and brought the red flags out as the air fence needed replacing as both riders required medical attention.
Quartararo was able to walk away with just some pain in his leg, but Oliveira had to be taken to the medical centre where he was diagnosed with a dislocated shoulder.
Source: Autosport