Before half-time, Singapore should have been up by at least 4 goals if Noh Alam Shah had taken all the chances that fell to him but it was not to be.
Midfielder Shahdan Sulaiman also wasted the first period final chance as he blasted over the bar when the Filipino defence fail to defend a cross.
After the break, Singapore went for the opener more intensely but once again, it saw more poor finishing.
It took until the hour mark before the opener finally came when a cross from Noh Alam Shah was headed in by Aleksandar Duric.
After that, Singapore had more chances to score the second but could not take it and then as the game progress, the national team unfortunately became more negative and started to pull back their punches.
They pay for it when a cross from the right was blasted into the net by Philippines Chris Greatwich.
Singapore will now have to win against Myanmar in two days time.
Suzuki Cup Group Stage
Scorer: Aleksandar Duric
Singapore: Hassan Sunny (GK), Noh Rahman, Baihakki Khaizan, Daniel Bennett, Juma’at Jantan, Fahrudin Mustafic (Isa Halim), Shahdan Sulaiman, Shahril Ishak, Fazrul Nawaz (Ridhuan Muhamad), Noh Alam Shah (Khariul Amri), Aleksandar Duric