He was waiting for the train at Paya Lebar MRT station when he spotted a "brown patch" on the East-West Line platform in April.
"I nearly stepped on this brown patch on the floor. On closer inspection, I realised it was a bat," said Mr Sean Yap.
The 22-year-old National University of Singapore (NUS) Life Sciences undergraduate was surprised, but quickly tried to salvage the carcass.
He said: "A train had just arrived, so my friend blocked passers-by from stepping on the bat as I used tissue to pick it up and placed it in a piece of bubble wrap.
"I didn't recognise the bat species and it was smaller and more fluffy than the common types in Singapore, so I salvaged it for the Lee Kong Chian Natural History Museum (LKCNHM) at NUS," he said.
He has tried to salvage other roadkill for the museum before.
It was indeed a bat not commonly encountered locally, according to Mr Marcus Chua, a museum officer at LKCNHM. There is only one other confirmed record of this species - the Javan pipistrelle - in Singapore.
Mr Yap explained: "The museum is always on the lookout for specimens because they prefer not to kill animals that are still living."
To others, a dead wild animal is a driving obstacle on roads, or a safety hazard. But to researchers at the LKCNHM, it is a potential animal specimen for study.
Mr Chua, 30, said: "In the past, people used to shoot and collect wild animals for studying.
"But as we experienced habitat loss and some species became rarer in Singapore, conservation became the priority. Recognising that, these groups rely mainly on salvaging dead animals for study."
Members of the public who spot roadkill notify the museum, which sends someone down to salvage it.
It is usually officers from the National Parks Board or friends of the museum who report on roadkill.
On average, the museum gets a roadkill sighting once every two months.
They are found anywhere, but especially at the periphery of nature reserves for mammals.
"When they wander out and find a road, they might decide to explore and get hit when a car comes," explains Mr Chua.