American Frances Tiafoe upsets No. 2 seed Rafael Nadal with win in fourth round of U.S. Open
24-year-old Frances Tiafoe put on the performance of his career on Monday at the U.S. Open, with a 6-4, 4-6, 6-4, 6-3 upset win over 22-time Grand Slam champion Rafael Nadal in the fourth round. Tiafoe, who has just