Hong Kong - Kenedy's offensive social media posts about China sparked calls for his club Chelsea to be banned from the country and were a spectacular own goal in a lucrative market.
Experts say that while the controversy will have only limited impact on Chelsea's popularity in China, it serves as a warning to European clubs chasing riches in the world's second-biggest economy.
The Brazilian's career at the Premier League champions was already on the wane when last week, while Chelsea were in China on a pre-season tour supposed to win new fans, Kenedy published two posts on Instagram that ignited a firestorm.
The first contained what many interpreted as a profanity aimed at China and a second showed a security guard asleep and the caption: "Wake up China. You idiot."
Kenedy and the club subsequently apologised but when the furore refused to die down Chelsea banished the 21-year-old from their Asia tour this week.
Chen Zhongjie, head of global strategic business at Chinese sports marketing firm Hupu.com, said Chelsea should have acted faster to apologise and punish the player.
"It is quite obvious that Chelsea didn't pay enough attention to this at the beginning, which led to the continuation of the negative impact," Chen said.
"It seems they are being pushed by public opinion instead of actively handling the issue. They still let Kenedy on the pitch after this (last Saturday against Arsenal in Beijing).
"This thing will blow over quite soon and the Chinese football fans will forgive Chelsea, but they will not forgive Kenedy.
"Chelsea's experience is a warning to other clubs - if you want to tap into the Chinese market you must be sincere and respectful."
'Shut your mouth'
The reaction in China to Kenedy's antics was fierce.
Even non-football fans condemned him on Weibo, China's equivalent of Twitter, some calling for Chelsea to be banned for insulting the country.
State media soon weighed in and an opinion piece in the People's Daily, the official mouthpiece of the ruling Communist Party, said the affair was "humiliating China".
"Even though Kenedy and Chelsea have apologised the matter cannot be dropped," raged the editorial.
"It should be said that today China is more and more powerful and confident.
"We may tolerate good advice, but we will not tolerate morbid behaviour that hurts China.
"To people who want to make trouble, please shut your mouth."
Mark Dreyer, a Beijing-based expert on sports business in China, said rabid comment in official media should not be overstated because it plays to a nationalist niche and is ignored by many Chinese.
"China being 'humiliated'? Of course not," said Dreyer, founder of the China Sports Insider website.
"The vast majority of people would not be able to pick Kenedy out of a line-up and don't care.
"I think this will all blow over pretty quickly because Kenedy is not a massive star and football fans tend to be forgiving of what their players do off the field.
"It certainly won't help them win over new fans but I'd be surprised if it drives current fans away."
It is a lesson for European teams in how quickly and fiercely controversy can rage in China at perceived slights to the country, experts say.
But it is also a warning for young footballers, especially when they are cooped up in hotel rooms far from home, said Rowan Simons, China-based author and expert on sport and media in the country.
"Young players - and people - should learn about the dangers of tweeting or sending information to social media and the repercussions that can have," he said.
"But definitely time to move on."