When ANZ Bank named Nuno Matos as its new chief executive in December, investors weren’t convinced that the former HSBC Holdings banker could easily turn around the lender, which is facing a litany of troubles.

With Matos set to start his role on Monday, anxiety is growing among ANZ’s senior executives that the 57-year-old Portuguese banker could take some forceful steps to clean up the Melbourne-based lender, including changes at the top echelon, to restore its reputation, according to people familiar with the matter.

Part of the trepidation is due to his relatively unknown status within the country, said those people, asking not to be identified discussing a private matter. To the outside world, Matos, who has a formal demeanour and is rarely seen wearing anything but a dark suit, is known for his direct and detail-oriented style of management, according to executives who have worked with him.

That could stand him in contrast to an often more informal corporate culture in Australia.