router.Host not working for me

[ikaasraa]

sd := router.Host("{subdomain:[a-z]+}.domain.com").Subrouter()
sd.Path("/").HandlerFunc(handlers.SubdomainHandler).Methods("GET")

router.HandleFunc("/", handlers.HomeHandler).Methods("GET")

it's not working ???
when I call / load HomeHandler
but when I call lh.localhost:300 again load HomeHandler instead SubDomainHandler