Women's singles player Gu Juan posted Singapore's lone victory in their Sudirman Cup opening tie against Denmark, beating Line Kjaersfeldt 21-16, 21-12.
But the Republic, ranked 14th in the world and playing in the top tier of the world mixed team competition for the first time, could not overcome the Danes in the other matches and went down 1-4.
Danny Bawa Chrisnanta and Vanessa Neo were beaten 21-11, 21-17 by world No. 4 Joachim Fischer Nielsen and Christinna Pedersen in the mixed doubles.
Chrisnanta and Terry Yeo were also no match for the world's top men's doubles pair, losing 10-21, 12-21 to Mathias Boe and Carsten Mogensen.
Neo and Yao Lei, a new partnership in the making, went down in straight games to world No. 3 pair Kamilla Rytter Juhl and Pedersen 19-21, 18-21 in the women's doubles.
In the men's singles, Derek Wong started off brightly and took a game off world No. 7 Jan O Jorgensen, but eventually lost 21-17, 9-21, 13-21.
Singapore are drawn in the same group as Denmark and Japan, the world No. 4 team. They play Japan on Monday.