In tennis, a ball boy's or ball girl's job is to quickly retrieve a ball and deliver it to the server as quickly as possible. At the same time, they are not allowed to interfere with live play. They are also required to stand in a corner with both arms behind their back. However, if a tennis ball serve comes at them at a speed of more than 100 miles per hour, there is an excellent chance they will not have enough time to brace for impact. Tennis ball boys do not wear protective cups during matches. I am sure that this ball boy from the Australian Open wishes that he did.