Mapping keywords/tags into content type via importer

So I have an importer that is mapping a column from a CSV file of keyword data into a term reference field in Drupal 7. The CSV column has the keywords (tags) in a comma separated presentation. So for example in the cell you'll see something like:

tag1,tag2,tag3

I have the term reference field as an autocomplete field set for "unlimited values" for user entry.

I've tested the import. The import works and imports all the keywords into the term reference field. However the tags are all presented in one comma separated line but as one tag. In other words they are not separate tags. They are all one tag. So it looks like the above but when you click on the link it just has piled all the keywords into one tag essentially. So they look like this on the node: tag1,tag2,tag3 but it's all one clickable tag. I want them to be separate tags.

Any suggestions on how to import them as separate tags without having to massage the data too much in the original CSV. Is this possible?

Best-

Trevor