Excel 14.1.4 (Office 2011 OSX)

I need to use a 'single sheet' Called MASTER of an Excel Workbook as a mail merge data source in Word. Word will not accept .xlsm files and as this workbook contains macros it has to have this .xlsm extension.

Is there a way to AUTOMATICALLY save a CSV file of a particular Worksheet in the this Workbook when I Save the Main File as normal. The CSV should go into the same location as the main file without popping up dialogues for overwriting etc.

Many thanks for your help.
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John