At the start he went on to win the under 15 boys National Short Course Swimming Championship in the year 2017 in which he became first in 50 metre breaststroke, first in 100 metre Breast stroke and second in 200 metre breast stroke.
In the same year in the National age group swimming championship in the under 15 boys category in the year 2017 again he became third in 200 meterbreast stroke.
In the year 2017 he was awarded the Rajans Maroons’ at the Colours Nite of the school and in 2017 again at the Zonal colours award ceremony he received the Zonal colours for the All Island National Schools games for swimming.
In 2018 he took part at the 54th Malaysia age group swimming Championship, and received school colours for representing Sri Lanka at an International Swimming meet. In the Sri Lanka Schools’ Aquatic Sports Association in the under 15 boys category he won the first place in the 100 metre breaststroke, second in 50 metre breaststroke and third in 200 metre breaststroke. At the All Island School games in 2018 he came first in both in 50 metre and 100 meter breaststroke in the under 16 boys contest.
In 2019, at the 45th National age group aquatic championship Sasmith came first In 50 metre breaststroke, second in 100 metres breaststroke and 200 metres breaststroke.
In the same year in the under 18 boys Swimming contest organized by the Sri Lanka Schools Aquatic Sports Association he became Second at the 50 metres breaststroke and in the same year at the All Island School games in the under 18 boys category he won second place at the same event and in the following year in 2019 he received Zonal colours at the Rajans Maroons Colours Nite for the All island National Schools games for swimming for the second time.
At present Sasmitha is studying in the Grade 12 class in the Mathematics stream and his intention is to do higher studies while continuing Swimming at the highest level to be selected as a National and International swimmer. He is especially thankful to his coach as well as his parents and the Principal of the School for the encouragement and guidance given to him to come to this standard in swimming as well as studies.