Sagan Tosu manager Kim Myung Hwi has tested positive for coronavirus, the J-League first division side said Tuesday.
Three club officials were found to have been in close-proximity contact with Kim, but no players, the club said.
Kim, a 39-year-old Japan-born South Korean, felt unwell around noon on Saturday, but his symptoms did not include a fever and he took part in an away match against Kashima Antlers that evening.
On Sunday evening he developed a fever of 38 degrees Celsius and underwent a polymerase chain reaction test at a hospital in Saga Prefecture the following day, where the test result came back positive.
The club had all players and staff tested for coronavirus on Tuesday. They expect to get the results before the Levain Cup match against Sanfrecce Hiroshima, which kicks off 7 p.m. on Wednesday.