Duffin, 28, has played two Tests and 23 one-day internationals, in which he has scored 80 and 546 runs, respectively.

Mawoyo is the seventh player to be replaced in the tournament after compatriot Sean Ervine, Nathan Hauritz, Michael Hussey (both Australia), Praveen Kumar of India, England's Eoin Morgan and Sohail Tanvir of Pakistan were earlier ruled out.