IN WHAT many commuters will see as a fitting end to its decade running Melbourne's rail system, the last train Connex will run is to be replaced by a bus.

Connex - which began running trains in Melbourne in 1999 when Victoria's railways were privatised - will hand over the rundown network to new operator Metro Trains in the early hours of Monday.

But due to track works around Laverton station, the final Connex service in operation will be a bus, leaving Newport station at 12.32am.

''The irony is apparent,'' said Connex spokesman John Rees, in his final day in the job.

''For anyone who wants to look at the more positive aspect of it, it shows we are doing a lot of track work at the moment.''