Giving a beating. What is the petroleum jelly for?

I was watching a rerun of Martin. At one point in the show Martin’s girlfriend is preparing to beat up another woman. Gina (Martin’s girlfriend), takes off her earrings, gets out a pair of gym shoes then pulls out a jar of petroleum jelly.
Taking off earrings is a sensible precaution. Gym shoes help give a firm base to throw a punch. But, petroleum jelly? Why would you need petroleum jelly to beat somebody up?

Boxers use it to prevent cuts on their face.

Although, I’m not sure it helps much in a street fight. Scratching, gouging, kicking is more than a little oil can handle.

Put it in your hair and it is very hard for your opponent to get a good grip. Um, so I figure, anyway.

Girls used to put it on their faces to minimize the scratches they would receive. They hardly used a closed fist to hit their opponent, and would look to scratch them to leave a mark to show what damage they’ve done. Nowadays, anything goes, even boxcutter, sadly. :frowning: