Osaka, top seeds book third round spots

Tokyo: Japanese medal hope Naomi Osaka sailed into the third round of the Tokyo Olympics on Monday, sweeping past 50th-ranked Swiss Viktorija Golubic 6-3 6-2, as other top seeds in the singles events also advanced.

Men's fourth seed Alexander Zverev brushed aside Daniel Elahi Galan of Colombia 6-2 6-2, while world number two Daniil Medvedev breezed through with a comfortable 6-2 6-1 win over India's Sumit Nagal. French Open champion Barbora Krejcikova continued her run of good form, taking out Canadian teenager Leylah Fernandez 6-2 6-4, while two-time Grand Slam winner Garbine Muguruza made short work of China's Wang Qiang, winning 6-3 6-0.