Educated at St. Peter's College, Colombo, Opatha joined the Royal Ceylon Volunteer Air Force in 1968. He had played for his college cricket team and went on to play for the air force cricket team until 1977. He first played for Ceylon in 1971 and was a member of the Sri Lankan teams in the World Cups in England in 1975 and 1979. He later played club cricket in Ireland for one season in 1979 and was offered the post of coach of the Holland team.[4]
As player/manager of the rebel tour to South Africa in 1982–83 in defiance of the sporting ban against the apartheid state, Opatha and the other tourists received a lifetime ban from international cricket. The name of the team, "Arosa Sri Lankan XI", derived from Opatha's initials ARO plus SA for South Africa. The ban was lifted in 1991.[5]
