Michael Gove, now a Tory frontbencher and key David Cameron ally, and Tom Baldwin, in The Times, said Mr Duncan Smith had been "steady under fire" and his shadow cabinet appointments - derided by modernisers for bringing in eurosceptics and right wingers - were starting to bear fruit.
Other cabinet members came under fire elsewhere, with Deputy Prime Minister John Prescott attacked and manhandled by demonstrators at a Labour Party rally in the North Wales.
Yet David Cameron has twice recently passed up the chance to fire his health secretary when first Liam Fox's and then Chris Huhne's resignations forced cabinet changes on him.