Garbine Muguruza cruised to victory in her first match as world No. 1, comfortably beating Rio Olympic champion Monica Puig in straight sets at the Toray Pan Pacific Open on Wednesday.
Wimbledon champion Muguruza, who unseated Karolina Pliskova at the top of the WTA rankings on Sept. 11, advanced to the quarterfinals with a 6-4, 6-0 win against Puig at Ariake Colosseum.
Puig had won their only previous meeting in the round of 16 at Rio last year, when the Puerto Rican stormed to the gold medal. But on Wednesday, it was all Muguruza, who played like the world's top-ranked player, while Puig committed far too many unforced errors to stand a chance.