The Dutch mentor knows all about what it takes to become a success in his homeland having played for Ajax Amsterdam for 12 years - where he won many domestic and European titles with the club during the 1960s and 1970s.
Serero is heading off to Amsterdam next month to link up with 'de Godenzonen' after his move from Ajax Cape Town was sealed recently.
Krol believes the 21-year-old has the ability to take the country by storm, but admits he cannot rely on his talent alone in the Eredivisie.
"Thulani has a big heart," Krol told The Sowetan.
"He will succeed if he works hard and listens to the instructions of the coaches in Amsterdam.
"He is a future Bafana Bafana star."