COLUMBUS, Ohio — Columbus Crew SC confirmed Wednesday four positive COVID-19 cases involving players following testing this week.

According to a press release from the club, no additional positive results for players or staff were received following additional rounds of testing Wednesday, results of which returned the same evening.

All MLS players undergo Polymerase Chain Reaction tests every other day, including the day before each match. The confirmation of a COVID-19 case occurs when a player receives two consecutive positive test results.

Upon receipt of initial positive results of two players Sunday, both players self-isolated under a strict and detailed protocol and extensive contact tracing and facility sanitization took place, the club said in the release.

After a scheduled off day Monday, two additional players had results that returned positive following Tuesday’s testing and self-isolated. The club will continue to test each remaining day this week and is scheduled to train Friday and Saturday ahead of Sunday’s postseason contest at home.

The Crew is scheduled to play Nashville SC in the MLS Playoffs at MAPFRE Stadium at 8 p.m.

The club said the health and safety of all players and staff remains the highest priority and the four individuals will remain in isolation, to be monitored by the club’s medical staff.

The club reported it has been in regular communication with Major League Soccer and local health authorities on the matter.