Beijiing Guoan coach Lee Jang-soo has offered to step down from his position after a shock less.
"Injuries hit my side just before the game," Lee told reporters.
"But it was not an excuse for the defeat today and I should be responsible for the woeful performance.
"I am prepared to relinquish my position as Beijing coach. If we continue to get stuck in this bad form, we won't be able to achieve our goal."
Beijing are still on top of the table despite the loss.