Cachirul (cah • chee • DOOL) is a term to refer to somebody who participates in an event (usually a sports one) without satisfying the requirements for participating. Such violation is typically done in secrecy and its ultimate purpose is to give the perpetrator an advantage.
Mexico's national sport, pambol, suffered international embarrassment because of the uncovering of cachirules playing for the national team against Guatemala in a qualifying game for the 1988 Olympic Games. Some players used fake birth certificates. As a result, el Tri couldn't participate in the 1990 World Cup in Italy.
The video below shows a very skillful 6-year-old playing soccer. The parents of the other kids surely thought he was a cachirul, a shaved-short dude.