Gabriel was ruled out of Melbourne and Sydney matches after injuring his left ankle last week during the innings and 212-run defeat in the first test in Hobart.
Barbadian right-armer Cummins, 25, has played one one-day international for his country and taken 99 wickets at an average of 22.83 in 36 first class matches.
West Indies play a tour match against Victoria in Geelong starting on Saturday before the test series resumes at Melbourne Cricket Ground on Dec. 26.
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Australia will be aiming for a series whitewash after cruising to victory within three days in Tasmania.
(Reporting by Nick Mulvenney; Editing by John O'Brien)
