World championship leader Fabio Quartararo extended his lead in the standings with a dominant victory at the Catalunya Grand Prix on Sunday as home favourite Aleix Espargaro threw away a podium position with an embarrassing mistake.
Yamaha's Quartararo, who started third on the grid behind pole-sitter Espargaro of Aprilia and Ducati's Francesco Bagnaia, stormed into the lead after the lights went out, overtaking both riders by turn one.
Frenchman Quartararo had struggled for grip on his Yamaha during practice but once he took the lead, he made no mistakes as he pulled away and quickly built a big advantage, forcing Espargaro to focus on the battle for second with Jorge Martin.
Espargaro looked set to finish runner-up but a premature celebration on the penultimate lap — having thought the race was over — dropped him down to fifth as Pramac Racing's Martin came second and his team mate Johann Zarco third.
SA's Brad Binder finished eighth. His brother Darryn Binder finished 12th.