Police were alerted to the incident in Glasgow’s Hope Street shortly after 1am on Sunday morning.
Scott Ferguson, 34, pounced on Dean McLean near Glasgow Central station in July last year.
The incident happened between Falkirk High and Glasgow Queen Street railway stations on Monday afternoon.
Police have released an image of a man they want to trace in connection with an assault on a Glasgow-bound train.
Passengers faced cancellations to trains on one of the busiest nights of the year.