SINGAPORE - Dipna Lim-Prasad has won her second silver medal and set a new 400m national record at the SEA Games on Thursday (Aug 24) at the Bukit Jalil Stadium.

The 26-year-old clocked 54.18sec in the race to erase Chee Swee Lee's 1974 record of 55.08sec set at the Asian Games in Teheran, Iran.

That record was the oldest national women's mark still standing.

Lim-Prasad finished behind winner Vietnam's Nguyen Thi Huyen (52.48sec). Thailand's Supanich Poolkerd claimed the bronze in 54.55sec.

Winning a silver in the 400m hurdles on Tuesday helped take a huge load off her shoulders, said Lim-Prasad.

"... My stress levels dropped significantly... I was super chill yesterday so I did everything I could to make sure I recovered properly and (that) my knee was ok."

She had injuerd her leg during a training stint in Japan and her participation in the Kuala Lumpur Games had been threatened. She had also come down with a virus for a month before that.

She added that she has been targeting to break the record for the past year, and remained confident after having come within a whisker before at the Thai Open in June, missing by just 0.02s.

"When I got silver I was just like okay, and Seng Song (her husband) shouted from the stands that I got the record... then it registered later on. (To clock) 54.18s is massive so I'm really happy."