The Singapore SEA Games in June saw the national men's 4x100m relay team set a new national record of 39.24 seconds, in the process clinching the Republic's fourth straight silver medal in the event.

But that high on June 12 has been dampened following the recent retirements of squad stalwarts Gary Yeo, Lee Cheng Wei, Amirudin Jamal and Elfi Mustapa.

Yeo, Lee, Amirudin and Calvin Kang had set the national record.

Only Kang and Naqib Asmin remain of the close-knit squad, who, with the exception of Naqib, trained full time in 2013 in a bid to land the elusive Games gold.

National sprint and hurdles coach Luis Cunha knows the colossal task that lies ahead as he seeks to recreate a team capable of challenging for honours in the region again.

He told The Straits Times: "It's going to be a challenge to build a new team. These guys are close, and have been together for many years.

"But I am hopeful we can do it. We're not talking about replacing athletes running under 10 seconds, so in that sense it is not impossible to help the new guys get there."

Cunha, who started work here last December, said he would shortlist potential runners and meet them and their coaches next month. That gives him more than two years to the next SEA Games, which will be held in Kuala Lumpur in December 2017.

The Portuguese, a former sprinter who competed in the 1988, 1992 and 1996 Olympics, said: "The relay is a team event in an individual sport. It means you need to train together often and have a certain level of commitment.

"I need to find out about the situation of the runners, whether they have national service or job commitments, to decide who to choose.

"Of course, this is a stop-watch event, and the 100m rankings will play a part (in selecting runners)."

The 50-year-old added that he aims to form a squad of 10 runners, and wants to hold his first centralised training by mid-October.

While he declined to name potential members, 21-year-old Donovan Chan, who holds the Schools National A Division 100m record; national Under-17 400m hurdles record holder Timothee Yap, 20; and Polytechnic-Institute of Technical Education Games 100m championship record holder Khairyll Amri, 22, are among those touted to replace the old guard.

Cunha said Kang, who competed in the last three SEA Games, would captain the new team and help integrate new members.

Like his coach, Kang, 25, said getting the new faces up to speed would be a challenge, but it is one he is relishing.

The Nanyang Technological University student said: "You need to have a similar aim and be willing to sacrifice individual interest for the team, because two will not run.

"Having said that, there is a bunch of other guys coming up. I hope to bring back what the old team had in terms of competitiveness, the willingness to fight for a place, and create an environment that spurs learning."

Cunha said he is optimistic that the new team can also finish on the podium in two years' time.

He said: "The goal is the same - to win a medal at the SEA Games. We know what are the steps we have to take. If we manage workouts and injuries, I believe it is possible."