The women's professional golf tour in Japan opened its season on Thursday following a roughly four-month delay due to the novel coronavirus pandemic, with the first round of the Earth Mondahmin Cup held behind closed doors.

Hinako Shibuno, the surprise winner of the 2019 British Open, and world No. 4 Nasa Hataoka, who has three victories on the U.S. LPGA Tour, were among the golfers who teed off after a one-hour rain delay at Camellia Hills Country Club in Chiba Prefecture, near Tokyo.

(Hinako Shibuno hits her tee shot on the 1st hole during the first round of the Earth Mondahmin Cup at the Camellia Hills Country Club on June 25, 2020, in Sodegaura, Chiba Prefecture)[Getty/Kyodo]

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Shibuno took a two-stroke penalty on the fifth green when she failed to put her marker back after lifting it so it wouldn't interfere with others' putts. It was a mistake she said she couldn't remember making before.

"I was in shock and I had to laugh to get past my anger," Shibuno said. "It took some time to get my feel for the game back."

She finished the day at even par in a tie for 59th.

The 72-hole tournament is the first event on the Japan LPGA Tour to be held without spectators, a protective measure many sports have taken against the spread of the virus. Instead, all four rounds will be broadcast live on the internet.

Some international players were unable to compete due to travel restrictions caused by the virus outbreak.

The Japan Ladies Professional Golfers' Association said Wednesday all 144 players and staff have been tested for the virus and none was positive.

Four events on the tour scheduled for July have already been called off because of the health crisis. The association said in May that it will combine the 2020 and 2021 seasons due to the cancelation of more than half of the events originally set for this year.