Liew competed only in the men's 100 m breaststroke at the 2000 Summer Olympics in Sydney. After winning a silver medal from the Southeast Asian Games in Brunei a year earlier, his entry time of 1:04.95 was officially accredited under a FINA B-standard. He challenged seven other swimmers in heat four, including two-time Olympians Valērijs Kalmikovs of Latvia and Arsenio López of Puerto Rico. Coming from second on the initial length, he faded down the stretch with a poor swim to a seventh seed in 1:06.41, almost 1.5 seconds below his entry standard. Liew failed to advance into the semifinals, as he placed fifty-seventh overall on the first day of prelims.