The International Table Tennis Federation (ITTF) threatened on Sunday to slap sanctions on China's national team after three top players quit a tournament in apparent protest at their head coach's removal.

The ITTF received a public apology from the Chinese team but it said it was taking the matter "extremely seriously" as it "damaged the image and the integrity of table tennis globally".

"Right now, all potential sanctions are on the table, and the ITTF will continue its investigation before any decisions are made," the sport's world governing body said in a statement.

The ITTF said the Chinese Table Tennis Association (CTTA) gave a preliminary statement but it requested a detailed report.

The sport's three top-ranked players — Ma Long, Xu Xin and Fan Zhendong — all failed to appear for their second-round singles matches at the prestigious ITTF World Tour Platinum China Open in the southwestern city of Chengdu on Friday. Two coaches also failed to show up.

The national team said in a public apology issued late Saturday that the players forfeited their matches "on impulse without fully understanding the details of the modifications that will be made to the management of the team".

"We have deeply realised the seriousness of this fault, resulting in ... damaging the team's positive social image of upholding patriotism, collectivism, and striving to fight for the glory of the country," it added.

Their no-show prompted China's top sports authority to order an investigation and reprimand the players, saying they had "ignored national honour and interests" and "disrespected the public".

The trio's elimination from the four-day tournament, which ends Sunday, came after they posted online protests over the removal of Liu Guoliang, who had been the Chinese team's head coach for more than a decade.

"At this moment we don't like to play anymore because we miss you, Liu Guoliang," the players said in identical posts on China's Twitter-like Weibo. The two absent coaches posted the same message.

Liu, a former Grand Slam champion, lost his coaching job in a restructuring announced by the CTTA on Tuesday, the official Xinhua news agency said, and was appointed CTTA vice-president.

The shake-up has been a hot topic in table tennis-mad China where the sport has a huge following.

Last month Kong Linghui was replaced as head of the women's table tennis team following a gambling debt scandal, sparking a social media frenzy.

The CTTA released a statement defending the changes, saying they aimed to "strengthen the team structure, reduce the level of management hierarchy, and improve the efficiency of the preparation for the Olympic Games."