At the 2000 Summer Olympics in Sydney, Sng drastically shortened his program, swimming only in the 400 m freestyle on the first day of the Games. He posted a FINA B-standard of 4:04.55 from the Southeast Asian Games in Brunei. He established a Singaporean record of 4:01.34 to hit the wall first in heat one, holding off Chile's Giancarlo Zolezzi by 0.17 of a second. Sng failed to reach the top 8 final, as he placed thirty-seventh overall in the prelims.