Tokyo - Olympic champion Monica Puig thrashed American Varvara Lepchenko 6-0, 6-3 at the Pan Pacific Open on Monday, her first victory since winning a stunning gold in Rio.
Puig beat Germany's Angelique Kerber in last month's Olympic final to nab Puerto Rico's first ever gold medal.
"A win is a win for me," shrugged the world number 33 after her first-round victory in rainy Tokyo.
"I'm just trying to finish the season strong and play some good tennis," added Puig, who crashed out of the US Open in the first round.
"The whole ride from the Olympics has been very crazy and very emotional so it feels good to settle down and play some good tennis again."
Elsewhere, wildcard Naomi Osaka overpowered fellow Japanese Misaki Doi 6-4, 6-4 to reach the second round.
The 18-year-old, born to a Japanese mother and Haitian father and who models her game on Serena Williams, seemed almost embarrassed after needing just 85 minutes to complete an upset victory.
"It was a close match but to be honest I felt like all the pressure was on her," world number 66 Osaka told reporters.
"I didn't feel any pressure at all so I wasn't nervous or anything."
Osaka, who can smack her serves at close to 200 kilometres per hour (124 miles per hour), will face either sixth seed Dominika Cibulkova of Slovakia or Czech Lucie Safarova after taking care of Doi, Japan's top-ranked player at 34th in the world.
"I have never actually won a match in the main draw at this tournament so this is a special win," said Osaka.
Two further first-round matches were postponed because of typhoon rains over Tokyo.