Commuting question?

Hi fellow melbournites

I'm here with a question related to bike commuting in Melbourne. The basics of it are - is there anywhere near Flinder's Lane (possible even Degraves st) where it is safe to lock up a bike? Or do I just lock it to a pole or something?

The reason is that I'm going to be doing a course on a Monday night in that area and I want to be able to ride my bike back to southern cross so I don't have to mess with the trains. Hiring one of those blue bikes also isn't an option because I'll be riding to get to Fairfield campus of NMIT earlier in the day as the closest railway station to there is about 2.5k.