Nepali swimmer Alexander Shah secured first position in the men's 100 m heat and set a new national record at the Tokyo Olympics on Tuesday.

The 18-year-old clocked 53.41 seconds to secure top finish in the heat 1 contested by seven swimmers at the Tokyo Aquatics Centre. He bettered his own national record of 55.38 seconds. The teenager, however, failed to make it to the next round — the semi-finals. The top 16 swimmers progress to the semi-finals. Only the swimmers finishing within 48.44 seconds qualified for the next rounds.

"I am super honoured to be here and represent Nepal. Although I am a bit disappointed (for not qualifying) I am still happy to break the national record," said Shah, adding that he would use the experience gained at the Games to learn more and work harder. "I still have a lot to learn. I don't race in the 50 m pool and I race only in the short course pool," he said referring to the 50 m pool he contested.

Among a total of 70 swimmers, Shah came in 59th position in the heats. He finished ahead of 11 swimmers. In the heat 1, Shah — who swam in the sixth lane — finished ahead of Kosovo's Olt Kondirolli, Palestine's Yazan Al Bawwab, Guyana's Andrew Fowler, Bhutan's Sangay Tenzin, Maldives' Nubal Azzam Ibrahim and Solomon Islands' Edgar Richardson Iro.

Italy's Thomas Ceccon secured the best timing of 47.71 seconds in the overall heats. USA's Caeleb Dressel (47.73 seconds) and Australia's Kyle Chalmers (47.77 seconds) secured top three finishes in the heats. The semi-finals will be played on Wednesday and final on Thursday.

Brazilian Cesar Cielo holds the world record with the timing of 46.91 seconds set in 2009.

Gaurika Singh will compete in women's 100 m freestyle heats on Wednesday.

Among the five Nepali athletes competing in the Games, judoka Soniya Bhatta and shooter Kalpana Pariyar made an early exit, losing in the first rounds.

Sprinter Saraswati Chaudhary will compete in the women's 100 m race on Friday.