Violence again erupts in Melbourne after major sporting event

Police are investigating after violence again broke out following a major sporting event in Melbourne.

Footage has emerged of two brawls outside Marvel Stadium after American Devin Haney defeated George Kambosos in the lightweight unification bout on Sunday.

In one of the videos a man lies motionless on the ground outside the venue as boxing fans continued to exchange blows.

In the other footage, four men can be seen throwing punches at each other.

Police say those involved in the brawls left the scene before officers arrived and no victims have come forward.

The violence comes after fights broke out outside the MCG after the AFL for two weeks in a row.