A pat on the shoulder means well done
A knock on the back, or the shoulder is a form of praise, a way of saying that good work has been done. It is a great congratulation that is widely used in the sports world. In a quick and clear manner, the congratulation is conveyed, without words. However, it does not have to be a positive outcome, but it can also be a bad outcome. When someone loses a match, it can get a pat, in which case it has the meaning of: good work done, unfortunately unsuccessful. In addition, it is also possible to use a pat on the shoulder as a consolation. The physical contact can be reassuring on a person who sits in the pit or needs to be comforted.
Pictures of shoulder pat.