The DeNA BayStars have issued a “severe warning” to 27-year-old outfielder Tomo Otosaka and ordered him to remain at home for breaking team coronavirus rules, the Central League club said Saturday according to Hochi Shimbun.

Otosaka was reportedly out at a crowded club, drinking until late at night at a time when the team prohibits going out unnecessarily.

“We’re not letting down our guard even for those saying they’ve been vaccinated in order to keep infections from spreading within the team,” team president Yota Kimura said.