195.13. Where a contestant receives a blow to the genitals or to the knee, the referee may interrupt the bout and allow up to 5 minutes for recovery.
If the contestant does not continue the bout after that delay, the referee shall:(1) following a blow to the genitals, indicate that the contestant has lost by abandonment;
(2) following a blow to the knee, disqualify his opponent.
However, sweep with the sole of the foot or the upper part of the foot against the opponent’s leg is permitted.