After making his international debut in 1967, Douglas quickly became a key influence as the midfield general in the heart of the Iraqi team. With the national team, he played in the 1974 World Cup qualifiers in Australia, where Iraq finished second behind the hosts, the 1972 and 1976 Asian Cups in Thailand and Iran, and in the Olympic qualifiers in 1968 and 1972. Douglas was also an important part of the Iraqi army team that won the 1972 and 1977 CISM World Military Championship. Douglas played for the Iraqi national team until 1978 and retired from playing a year later.