In loco parentis a sporting example?

A great example of this can be when there is a football team, the coach who is there who has to be over the age of 18, should be on look out for things as bad tackles playing quality. a great one to use is say if there is a game what involved 17 year old, and say a 14 year old tried to get involved, if this younger player got hurt or injured this will be the coaches fault as he did not exclude or stop him from playing with the older group of footballers