Photo: © 2010 AAP/JOE CASTRO

Hobart's Tim Redmond was in Melbourne to catch some AFL on the weekend.

On the way back to his accommodation, his train came under siege from a group of up to ten teenagers.

When the train pulled up at one station, a passenger was dragged from the train and threatened with broken bottles by four of the attackers.

When Redmond stepped in, he was smashed in the head with a rock, a blow that left him with a brain clot.

His father, Mark, has described him as son as "hero".

“He decided to step in … and make a stand. He’s a pretty compassionate guy,” Mark Redmond told the Herald Sun.

While his son is in a stable condition, his father says he is angry about what happened.