Defending Chinese FA Cup champions Shanghai Shenhua were forced to issue a public apology on Wednesday evening after they were knocked out of this year's competition by third tier side Nantong Zhiyun.
Shenhua threw away a two-goal lead to lose 3-2 and exit the competition in the fourth round, when Chinese Super League sides enter the competition, and comes just five months after winning the title for the first time since 1998.
"For the last two games, the team has had problems both in attack and defence and those will be reviewed by the team," the club said in a statement posted on social media.
"We're sorry to the many fans who came to support us, and apologise to those who care about Shenhua. We will not forget what has happened tonight."
The loss follows a 5-1 thrashing in the Chinese Super League at the hands of Jiangsu Suning on Sunday evening that saw Shenhua slip to seventh in the standings.
Shenhua fielded a side that featured none of their foreign players, but were still overwhelming favourites to advance to the next round.
Gao Di put Wu Jingui's team in front after 11 minutes and Wang Yun's penalty 12 minutes before the break doubled the Shanghai side's advantage.
But an own goal by Aidi Fulangxisi gave Nantong a foothold in the game just before the hour mark and further goals from Hu Ming and Ji Jun, who scored eight minutes from time, earned the China League Two side a famous win.
"To lose this kind of game, especially when you are the champions, is very bad," said Wu. "It's also hard for the fans. We apologise and hopefully we can lift ourselves by winning our next league game."
Two other Chinese Super League side also exited the competition at the hands of lower league opposition in the fourth round, with Henan Jianye losing out to Shenyang Urban and Changchun Yatai defeated by Sichuan.