J. League side FC Tokyo suffered their first Asian Champions League loss on Tuesday, falling 1-0 to China's Shanghai Shenhua on a 72nd-minute Yu Hanchao penalty.
The loss at Education City Stadium in Al Rayyan, Qatar, left Tokyo third in Group F, with the first two teams qualifying for the knockout round.
"In this kind of competition, teams that get on the front foot end up on top, so the next game that we play (on Friday) is crucial for us," FC Tokyo manager Kenta Hasegawa said. "We have adjustments to make in a very short time."
The game turned on a long ball into the FC Tokyo penalty area in the 70th minute, when defender Hotaka Nakamura inadvertently brought down his man and was sent off.
The J. eague side failed on their best chance to score, when Diego Oliveira's volley was saved in the 39th minute.
Two other J. League teams will be in action in Qatar on Wednesday. Vissel Kobe play China's Guangzhou Evergrande in Group G, while Yokohama F. Marinos take on Shanghai SIPG, another Chinese team, in Group H.