In a matchup of rising U.S. players, fifth-seeded Alex Michelsen defeated Learner Tien 6-4, 6-2 on Monday in the first round of the U.S. Men's Clay Court Championship in Houston.

been considered a risk only to elite professional sportspeople. While it has been found in the brains of those involved in AFL, rugby, hockey, motocross and boxing, studies have now found victims ...