...I remember Rikki Herbert playing in that first qualifying game vs Australia on our run to the 82 World Cup, much criticism, not ready for international football etc - look how that ended up...
Also, Wynton Rufer debuted for the All Whites at aged 17 and was at the World Cup Finals playing powerhouses Scotland (at the time), the USSR and Brazil at aged 19. If you're good enough...
'Keepers often need big, bold personalities. That might be difficult at aged 18.