Two Yomiuri Giants players have tested positive for the new coronavirus, the Central League team announced Wednesday, casting a shadow over Nippon Professional Baseball's plan to start the 2020 season on June 19.

Giants shortstop Hayato Sakamoto and catcher Takumi Oshiro are the first pro baseball players in Japan known to have tested positive for the pneumonia-causing virus since Hanshin Tigers pitcher Shintaro Fujinami and two teammates were infected in late March.

On May 27, two days after the June 19 date was set, the Giants announced that roughly 220 people in the organization would be tested for coronavirus antibodies. According to the team, the polymerase chain reaction tests taken by Sakamoto and Oshiro both showed only traces of the coronavirus.

In order to limit the further spread of the virus, the Giants canceled Wednesday's practice game against the Seibu Lions.

NPB started playing practice games Tuesday after settling on a June 19 start to the season. A 143-game campaign that was due to begin on March 20 has been shortened to 120 games due to the delay. The contests were going to be held behind closed door initially.