At 33, Villas-Boas' appointment is seen as a huge gamble but Grant believes the Portuguese can be as a big a success as one of his predecessors Jose Mourinho.
"Andre's very young but he's been involved in a football a long time," Grant told talkSPORT.
"We need to remember that when Jose came he didn't have much more experience than him. He was at Porto for two years. And Pep Guardiola came straight into the Barcelona job after managing Barcelona B."