Back in action for the first time since his second-round exit at the Australian Open, top-seeded Frances Tiafoe posted a victory Thursday in the second round of the Dallas Open. Tiafoe, who received a first-round bye, downed Alex Michelsen 6-4, 6-3 in a matchup of U.S. players. In the 78-minute match, Michelsen had a 9-1 edge in aces and compiled more winners (22-15) but made twice as many unforced errors as Tiafoe (10-5). Seventh-seeded Jordan Thompson of Australia also had a smooth day’s work, beating the United States’ Denis Kudla 6-1, 6-1. Eighth-seeded Dominik Koepfer of Germany ousted Australia’s Rinky Hijikata 6-3, 7-6 (5), and fourth-seeded Adrian Mannarino of France got a walkover when Japan’s Yoshihito Nishioka due to nausea. Open 13 Provence The top two seeds produced straight-set wins in the second round at Marseille, France. No. 1 Hubert Hurkacz of Poland thrashed Kazakhstan’s Alexander Shevchenko 6-1, 6-4, and No. 2 Grigor Dimitrov of Bulgaria downed the United States’ Sebastian Korda 6-1, 7-6 (5). Hurkacz rode a 13-3 advantage in aces and a 81 percent first-serve success to his 65-minute win. Dimitrov also won 81 percent of the time on his first serve, and he saved two of the three break points he faced. Fifth-seeded Alejandro Davidovich Fokina of Spain eliminated Finland’s Emil Ruusuvuori 6-3, 7-5. China’s Zhang Zhizhen upset seventh-seeded Felix Auger-Aliassime of Canada 6-4, 6-4, and France’s Arthur Rinderknech topped eighth-seeded Jiri Lehecka of the Czech Republic 7-5, 7-6 (5). Cordoba Open Rain washed away most of the Thursday action in Cordoba, Argentina, as just one match was completed. Luciano Darderi, an Argentinian qualifier, downed fourth-seed Sebastian Ofner of Austria 6-0, 6-3 to make an ATP quarterfinal for the first time. Another Argentinian qualifier, Roman Andres Burruchaga, led seventh-seeded Yannick Hanfmann of Germany 6-3, 1-6, 2-1 when their match was suspended due to rain.