He already looked pale and listless while waiting to start his men's 1,500 metres race at the Singapore National Swimming Championships last night.
As the swimmers ploughed through their 30 laps at the OCBC Aquatic Centre, national record-holder Teo Zhen Ren's strokes looked rushed as he slowly faded away from race leaders Pang Sheng Jun and Benedict Boon.
Boon, 18, eventually won the distance race in 16min 03.63sec to set a new meet record, while Pang, 22, clocked 16:09.01 to take silver.
Teo, 20, took third place with 16:11.34, but all three medallists failed to make the South-east Asia (SEA) Games 'A' qualifying time of 15:57.98.
Swimfast Aquatic Club (SAC) swimmer Teo said: "I have been having a flu since early this week and I thought I would recover in time for this event.
"I have a runny nose and I was really struggling midway through the race."
A casual look at his recent timings shows that he has yet to regain the form he showed before enlisting for National Service in February last year.
He took over the national record in the event from Marcus Cheah when he clocked 15:55.34 at the ASEAN Schools Games in 2011, and had steadily lowered his times till the South-east Asia Swimming Championships in 2012, where he set his present national mark of 15:43.08.
He picked up the SEA Games gold medal in 2011 in Palembang in 15:44.32, but finished only in fifth place last year in Myanmar with a time of 16:10.97.
At the Incheon Asian Games in September, he clocked 16:08.75.
SAC senior coach and incoming national assistant coach Gary Tan said: "We would need to go back to the drawing board and review some issues because he had been training well before this (meet)."
Even with his illness, the loss last night stung Teo, and he knows he has a mammoth task ahead of him for the home SEA Games.
He said: "I haven't had a full training cycle since this meet is rather close to the Asian Games.
"Of course I hate it when I lose because I haven't lost (to another Singaporean) in this event on home soil for a while.
"But now I am more motivated to train even harder; I have to be the best in Singapore before I can aim for the SEA Games gold, right?"
SWIMMERS WHO MADE THE SEA GAMES 'A' QUALIFYING MARKS
Men's 50m fly (24.66sec): Quah Zheng Wen, 24.62 (meet record)
Women's 50m breast (33.39): Roanne Ho, 32.99 (meet record)
Women's 400m free (4min 21.24sec): Rachel Majorie Tseng, 4:18.70
Men's 1,500m free: Benedict Boon, 16:03.63 (meet record)
This article was first published on December 21, 2014.
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