- They helped guide Balestier Khalsa to four trophies over the past two seasons.
But Tigers' S-League coach Darren Stewart and his assistant Kevin Wee - who also acts as the club's Prime League (Under-21) coach - will no longer be with the club next season.
Balestier chairman S Thavaneson confirmed this with The New Paper on Wednesday.
"He (Stewart) is contracted until the end of 2013, and we will not retain him for next season," said Thava, adding that Wee will also be released.
Stewart (right) and Wee could not be reached for comment on Wednesday night.
Former Australia international Stewart guided the club to their first piece of silverware since the S-League was formed in 1996, when the team lifted the StarHub League Cup in July.
He also guided the club to their best finishes since the merger of Balestier Central and Clementi Khalsa in 2003, and was shortlisted for the S-League Coach of the Year award in each of the last two seasons.
Balestier finished sixth in 2012 and fourth in the recently-concluded season.
His long-time assistant Wee, meanwhile, led the Tigers' Under-21 side to back-to-back Prime League titles, as well as last year's FA Cup.
While Thavaneson declined to go into why he decided not to renew the duo's contracts, he hinted that it was not because of football reasons.
A Balestier player, who spoke on condition of anonymity, told TNP: "We players heard about it on Tuesday and we are all disappointed.
"We pride ourselves on being a united team, so this comes as a big shock to us.
"Darren and Kevin have played key roles in bringing success to this club, as well as the first major silverware in the League Cup.
"And they always shun the limelight, and prefer to let the players take all the credit.
"Some of us have already signed on to play next season and it is sad that Darren and Kevin won't be with us."
Meanwhile, RHB Singapore Cup runners- up Tanjong Pagar United yesterday announced that coach Patrick Vallee signed a two-year extension to his contract at the club.
COMMENT - after ditching the most successful coach in their history I can only imagine Balestier Khalsa have lined up Mourinho. Or Wenger.