The 2018 S-League season could kick off with eight teams instead of nine after Brunei DPMM FC, champions in 2015, announced on their official website late on Monday that they are planning to play in the top-tier Indonesian league next year.
This development came after club officials met the Football Association of Singapore (FAS) on Monday to discuss the new regulations for the upcoming season.
On the same day, the national body announced revamp plans aimed at reviving the Republic's professional football league, which starts on March 31 next year.
An age quota aimed at giving younger players more exposure will be imposed on the six local clubs while Japan's Albirex Niigata, the league's other foreign side, will also be subjected to restrictions.
For a 21-man squad, two-time defending champions Albirex must have nine Under-21 players, nine U-23s and only one player of any age. They will be allowed to sign two U-23 Singaporeans.
It is unclear if similar rules will apply to DPMM, but The Straits Times understands the meeting with FAS did not go well.
DPMM officials could not be contacted for comment yesterday. But a source close to the club said that while they respect the FAS' decision to focus on youth, the age restrictions and a reduction in the foreign player quota to two will hurt their ability to be competitive.
They had Chileans Vincent Salas and Daud Gazale and Brazilian Rafael Ramazotti on their books this year, while the rest of the squad were Bruneians. No Singaporean has played for the club.
DPMM were invited to join the S-League in 2009 and won three League Cups before their 2015 league success. They finished eighth among the nine teams last season.
It is understood that the club had signed a contract to compete in Singapore's domestic competitions this year, and that the deal comes with an option to renew for another year.
DPMM also revealed on their website that they had sought to join the Malaysian league but that move fell through. They were asked to take in Malaysian players, with Bruneians considered as foreigners and subject to quotas, and play their home games in Malaysia.
FAS president Lim Kia Tong told this paper: "We knew that their attempt to participate in the Malaysian league wasn't successful, but they did not indicate that they wanted to play elsewhere next year."
He declined to reveal details of his meeting with DPMM officials but said: "We made it clear that Singapore, and in particular the FAS, has always treasured their participation in our league.
"DPMM have been participating in our league for a number of years and they've acquitted themselves very well, both on and off the pitch.
"They are a crystal clear example of clean sporting spirit.
"We made it clear that we do want them to continue to participate in our league, and we will do what we can to accommodate them for this to continue."