The record of his 19-month tenure reads: Twenty-one matches, 14 losses, five draws and two wins.
The national football team are in the midst of a 13-match winless run over a year and, add in the Lions' failure to qualify for the 2019 Asian Cup Finals, Sundram's record makes for painful reading.
The 0-3 qualifying defeat by Bahrain on Tuesday was played before only 2,628 fans at the National Stadium, a clear sign that local supporters have lost patience with a team now synonymous with defeat.
Sundram, 52, became the Lions' first Singaporean coach in 16 years when he took over from German Bernd Stange in May last year. His contract ends in March 2019.
It has been a year since the Lions tasted victory in a 1-0 friendly win over Cambodia on Nov 13, 2016 and the big question is whether he is the right man for the job.
His predecessor Stange feels that Sundram made a mistake by not sticking with youth, instead recalling veterans such as Daniel Bennett, 39, and Fahrudin Mustafic, 36.
"Sundram is moving in the wrong direction. He likes oldies and doesn't like attacking football. The future of Singapore football is youth but not with Sundram," the 69-year-old told The Sunday Times.
A former Singapore international blamed the Lions' poor results on Sundram's style of football.
Speaking on condition of anonymity, the ex-Lion said: "It's hopeful football, that's all it is, and it's shameful to keep playing like this. With the players that we've got, we can surely do much more. For sure, Sundram has to go.
"After just 15 minutes of watching the game against Bahrain, you could see what the Lions were trying to do. Even after Bahrain figured them out, they did nothing."
He also took issue with the players that Sundram has picked in his various squads.
"You can't pick players based on reputation, they must be selected based on form," he said.
Some critics have called for the Football Association of Singapore (FAS) to find a foreign coach, but former Woodlands Wellington coach Shasi Kumar believes Sundram should be given more time.
"I can't think of anyone who can come in now and get good results with this group of players. He's got to be a magician who's able to change how the local footballers play," said Shasi, who laments a lack of a pipeline for the national team.
"People are asking why we're not playing attacking football with younger players. I've been a player and a coach, and I don't think they know what they're taking about. I believe Sundram's hands are tied."
Patrick Ang, the former chairman of the FAS' National Teams Committee (NTC) - a now-defunct committee that directed and managed the affairs of Singapore's various national football teams - blames the Lions' malaise on a failed youth development system.
"We are paying the price for the decisions of past administrators who did not take youth development systems seriously," said Ang.
"The players coming through the ranks aren't good enough, and the attitude and culture here are all wrong."
Having worked as Sundram's assistant in the LionsXII side that won the Malaysian Super League in 2013, and helped with the Lions in their games against Hong Kong and Turkmenistan two months ago, national women's coach K Balagumaran agrees with Ang on the players' attitude.
"It is not easy to drill tactical discipline into a team, but Sundram managed that with the LionsXII when most of the national team players were younger. So why are things different now?" said Bala.
"True, the LionsXII played only against Malaysian club sides, but the unity and winning mentality were there.
"When I worked with him during the Hong Kong and Turkmenistan games, it wasn't there. I'm still trying to figure out why."
During his first year in charge as caretaker coach, Sundram was tasked with qualifying for the semi-finals of the 2016 Suzuki Cup.
That target was not met as the Lions were booted out in the group stages, but Sundram's contract was extended for another two years in March this year.
He was then tasked with leading the Lions to the 2019 Asian Cup Finals, a quest that ended even before the final group fixture against Chinese Taipei next March.
Former FAS director of coaching Seak Poh Leong, who helmed the national team between 1987 and 1988, feels that the FAS cannot remain silent on Sundram's situation.
"The FAS Council should come out to say that he didn't meet his target and sack him. If they feel that he has done enough despite the results, then back him until the next Suzuki Cup (next year)," said Seak.
"If the FAS' direction is to build a new team, they need to say how much time Sundram will be given to do this. But, having said that, any coach will still have to be responsible for the results of his team."
When asked about Sundram, the FAS Council declined to comment at its annual congress on Thursday.
The FAS has unveiled a rescue plan for Singapore football that is targeted at developing the next generation of players. Seak believes that is the right move forward.
"We have to accept that Singapore football has been buried because youth development has failed miserably," said Seak.
"At least the FAS is making moves to focus more on development, because with the players that we have now, even if we bring in Sir Alex Ferguson, he'll have no chance.
"We have a long way to go before we finally see the team improve."
• Additional reporting by David Lee