A single leg Boston crab is a variation on the basic Boston crab. Both of these holds are vicious and almost guaranteed to extract a quick submission from the stricken victim, but – if at all possible – the single leg Boston is probably even more efficient than the full one.

With the victim face down on the mat, the attacker hooks one of her legs under her armpit, gets hold of the knee and pulls it backward, sitting back onto her opponent’s back.

A move used both in professional and in competitive mat matches, the single leg Boston leaves little room for escape. While in the case of a regular Boston crab the victim may be able to power her way out flipping her opponent forward, in the case of the Single leg Boston, she is not likely to muster enough strength through the single leg involved in the hold.

Possible escape: if the attacker manages to properly sink the hold in I’d say the only escape is through surrender.

Rating:  a truly effective weapon, the single leg Boston is guaranteed to put a quick end to your match.