On the latest episode of WWE Monday Night RAW, Rey Mysterio & Aleister Black defeated Seth Rollins & Murphy via disqualification.

The finish seemed strange, as Mysterio was going to hit a 619 on Murphy when Rollins, while outside of the ring, caught Mysterio's legs in the ropes and slammed him to the floor, as seen in the video above. Despite Rollins being part of the match, Rollins & Murphy were disqualified.

Bryan Alvarez revealed on Wrestling Observer Live that there is a little-known rule where the illegal man in a tag team match can't attack the other team's legal man. The one exception is to break up a pin. Also, when there is a legal tag, both the person that was tagged in and the wrestler going to the apron can beat on the opposing team's competitor for five seconds.

However, if you're the legal man, you are allowed to hit the other team's illegal man, even though the illegal man can't touch the competitor who is legal. Also, both illegal men can fight with each other.

According to Alvarez, Vince McMahon is adamant that this rule be enforced. Wrestlers have apparently had to nix spots in matches in the past because they violated this rule.

Here's the gist of how it works using the Mysterio & Black vs. Rollins & Murphy match as an example, assuming Mysterio and Murphy were the legal men:

* Mysterio can attack Rollins, since Mysterio is legal and Rollins isn't.
* Rollins can't attack Mysterio, unless Rollins is breaking up Mysterio pinning Murphy.
* Rollins and Black can attack each other.
* If Murphy tags in Rollins, both men can beat on Mysterio for five seconds.