American No 4 seed beats Belinda Bencic 6-3, 1-6, 6-3 in quarter-final Gauff next faces 13th seed Karolína Muchová for a place in final American No 4 seed beats Belinda Bencic 6-3, 1-6, 6-3 in quarter-final Gauff next faces 13th seed Karolína Muchová for a place in final Coco Gauff may be struggling with an unfamiliar arm injury, indifferent form and the pressure of attempting to transform her serve with the entire tennis world watching, but the one quality that will never evade her is her