ˈɛsteɪ mˌeɪd hɪz deɪbjˈuː fɚðə sˈiːnjɚ nˈæʃənəl skwˈɑːd ˌɔn ɑːktˈoʊbɚ sˈɛvəntˌiːn, nˈaɪntiːnhˈʌndɹɪd nˈaɪnti, ɪn ɐ fɹˈɛndli ɐɡˈɛnst bɹɐzˈɪl.
Estay made his debut for the senior national squad on October 17, 1990, in a friendly against Brazil.