• Gauff, 15, stuns No 3 seed 6-3, 6-4 in 67 minutes• Venus Williams says ‘sky’s limit’ for precocious teenagerThere is precocious composure and there is Coco Gauff. It is difficult to recall a teenager thrown into the klieg lights of global sporting celebrity so comfortable with praise yet unfailingly polite and brimming with such self-belief. Anyone who moves into her ambit would think the same: is she too good to be true?
Certainly, she was too good for Naomi Osaka here on Friday night. In an hour and seven minutes she destroyed the defending champion for the loss of seven games. No mountain is safe. Ask Venus Williams, who won four of her seven slams before Gauff was born, but could not take a set off her in two matches in slams, most recently here this week.