Pierre Gasly was replaced by Brendo Hartley at the United States Grand Prix of the 2017 Formula One World Championship .
Sainz 's seat at Toro Rosso was taken by Daniil Kvyat who returned to race for Toro Rosso again , while FIA World Endurance Championship driver and former Red Bull Junior Team member Brendon Hartley replace Pierre Gasly at the United States Grand Prix.
2017 Formula One World Championship