pɹˈaɪɚ tə nˈaɪntiːnhˈʌndɹɪd sˈɪksti fˈoːɹ ðə dᵻfˈɛndɪŋ tʃˈæmpiən nˈeɪʃən hæd ɹˈɛɡjʊlɚli hˈoʊstᵻd bˈoʊθ ðɪ ˌɪntɚzˈoʊn plˈeɪɔfs ænd ðə tʃˈælɪndʒ ɹˈaʊnd, bˌʌt ɐ ɹˈuːlz tʃˈeɪndʒ ɪfˈɛktɪv ðæt jˈɪɹ pɹɪvˈɛntᵻd ðə sˈeɪm dᵻfˈɛndɪŋ tʃˈæmpiən nˈeɪʃən fɹʌm hˌævɪŋ ðɪs ɐdvˈæntɪdʒ fɔːɹ tˈuː səksˈɛsɪv tˈɑːməs kˈʌp sˈiːzənz.
Prior to 1964 the defending champion nation had regularly hosted both the inter-zone playoffs and the challenge round, but a rules change effective that year prevented the same defending champion nation from having this advantage for two successive Thomas Cup seasons.