Both Harimau Muda and Geylang were leading by a goal against Balestier and Gombak respectively, but the matches were halted after about an hour and subsequently called off.
Harimau Muda were leading 1-0 in their match against Balestier Khalsa thanks to an 11th minute goal from Thamil Arasu, while Gombak United were trailing by a similar scoreline to Jozef Kaplan's 45th minute strike for Geylang United.
Heavy rain at the Yishun and Bedok stadiums saw the games being halted temporarily in the 64th and 67th minutes respectively, with the authorities subsequently deciding to abandon both matches.
It is understood that both fixtures will be rescheduled to a later date.
The Football Association of Singapore has advised ticket holders to retain their stubs for the rescheduled matches, and stated that the dates for the replays will be released in due course.