SAR midfielder So Chun-yin missed a chance right at the start when his header went just wide of the post. But Shanghai hit back in the 12th minute when forward Wang Weidong scored the only goal of the game after a brisk attack.
The match was played at a fast pace, and several Hong Kong players suffered injuries. Captain Shek Tsz-fung was taken off after hurting his leg, while striker Wong Sheung-choi suffered a cut lip after being accidentally kicked by a Shanghai player.
"It's not a big deal except it was quite painful at the time," said Sheung-choi after the match.
"We are doing quite well, but I hope to combine with Chun-yin better to create more opportunities for the team."
With more matches to come, the Hong Kong boys are still confident of qualifying from the group stage of the competition.