The Norwegian Casper Ruud, 5th in the world and finalist last year, gave up a set on Monday before qualifying with difficulty for the second round of the US Open by dismissing the American from qualifications Emilio Nava (154th) 7-6 ( 7/5), 3-6, 6-4, 7-6 (7/5). In the next round, the 24-year-old Norwegian will face Chinese Zhizhen Zhang (67th), winner of American J.J. Wolf (45th) 7-5, 7-5, 6-7 (5/7), 4-6, 6 -3.