Several Bundesliga players are being tested daily and receiving same day results after coronavirus cases were discovered in their squad.
Cologne have ramped up their player checks following the three positive tests revealed on Friday, a development that will alert the Premier League as they monitor how Germany are attempting to resume football amid the coronavirus pandemic.
The trio of players were put in a 14-day quarantine though training was able to continue.
The remaining members of the training group the infected players were part of are currently being checked every 24 hours.