If a player collapses with no suspicion of a spinal injury and is found to be breathing and have a pulse but remains unconscious then they should be placed in the recovery position to assist their airway.
There are several different techniques described in the literature, we will describe one of these. Place the patients arm nearest to you out at 90° with the elbow flexed at 90°. Take the arm furthest away from you and bring the palm of the patient and support this against the cheek of their face. Using your other hand to either grip the patients waist band or their flexed knee role the patient onto their side protecting their head preventing it from hitting the floor.
Once the patient is rolled position their legs to prevent them rolling back ensuring they have an open airway and are breathing.
Keep observing the patient until help arrives carrying out regular observations. If possible administer oxygen via a non rebreathe mask.