Singapore were held to a 2-2 draw by Macau at the Macau University of Science and Technology on Monday evening, in their second match of the international week.
A brace from LionsXII striker Khairul Amri saw Singapore enter the break two goals to the good.
However, defensive lapses in the second-half allowed Macau back in the game.
Leong Ka Hang and Nicholas Torrao scored to cap off a well-deserved comeback.
The Republic had lost to Hong Kong 1-2 last Friday. Their next match is against Bahrain on Nov 7, shortly before the Nov 22-Dec 20 Asean Football Federation Suzuki Cup, where Singapore are the defending champions.