PARIS (Reuters) – Teenager Coco Gauff downed veteran Kaia Kanepi in a clash of the generations to reach the fourth round of the French Open with a 6-3 6-4 victory on Friday. The 18-year-old American, who was still a toddler when Estonian Kanepi, 36, played the first of two quarter-finals at Roland Garros in 2008, will next face Belgian 31st seed Elise Mertens.