Beat up and Mug

Beat up verb - Give a beating to; subject to a beating, either as a punishment or as an act of aggression.

Mug and beat up are semantically related In some cases you can use "Mug" instead a verb "Beat up".

Mug verb - To distort one's face.

Beat up and mug are semantically related in attack topic. Sometimes you can use "Beat up" instead a verb "Mug", if it concerns topics such as assault.