Beijing Guoan coach Lee Jang-soo is ruing missed opportunities after the 1-0 loss to Ulsan Hyundai overnight.
The loss left Beijing in a precarious position in Group E of the Asian Champions League, four points behind leaders Nagoya Grampus and two in arrears of Ulsan.
"The first half of the match was exciting, and both sides played physical, skilful football," said the Korean.
"We tried to stop the other team getting close to our penalty area and in the second half we pushed players up-field hoping to score goals.
"We had some good chances near the end, but we didn't score.
"We were man-marking in defence, but lots of unexpected situations arose during the game which upset our plan and allowed Ulsan to score.
"Now it looks like we'll struggle to win the group, our situation is very difficult now," Lee added.