In 1959, Matsui Dar, a Japanese swimming trainer, became his coach and participated in the South East Asian Games in Bangkok and wrote new records in 100 metres and 200 metres freestyle swimming.
In 1959, Mr. Matsui Dar, a Japanese swimming trainer, became his coach and Tin Maung Ni can have learned swimming systematically. In that year, he could participate in First South East Asian Games in Bangkok and wrote new records in 100 metres and 200 metres freestyle swimming.