Chelsea say they are "disgusted" after right-back Reece James was racially abused on social media.
James, 21, posted a screenshot of racist messages he had received via Instagram on Friday, with the caption "something needs to change".
"This club finds racism and all forms of discriminatory behaviour completely unacceptable. We totally condemn it," Chelsea said in a statement.
James is the latest player to receive racist abuse on social media this week.
On Friday, West Brom contacted the police over an alleged racist message sent to midfielder Romaine Sawyers, with West Midlands Police since confirming the arrest of one man.
Manchester United players Axel Tuanzebe and Anthony Martial were also racially abused on social media after Wednesday's home defeat by Sheffield United.
"In sport, as in wider society, we must create a social media environment where hateful and discriminatory actions are as unacceptable online as they would be on the street," Chelsea's statement added.
"We add our voice to those urging social media platforms and regulatory authorities to take stronger, more effective and more urgent action against this despicable behaviour.
"Something needs to change and it needs to change now."
Earlier on Friday, Premier League chief executive Richard Masters condemned the abuse received by players, saying he was "appalled".
"Racist behaviour of any form is unacceptable and nobody should have to deal with it," he said.
"Tackling online hate is a priority for football, and I believe social media companies need to do more."
He said the Premier League had "regular dialogue" with social media companies, adding: "We want to see swifter removal of offensive messages and improved identification and banning of offenders."
The Professional Footballers' Association, the players' union, has encouraged players targeted by racial abuse to press charges.
On Monday, the UK government held talks with current and former footballers about tackling discrimination and abuse.
The government plans to introduce new laws on online abuse this year and the Premier League has launched its own online abuse reporting system.
A spokesperson for Facebook, which also owns Instagram, said: "There is no place for racism on Instagram and we are committed to removing it when we find it. We know there is more to do and we will continue to work closely with clubs, players and football authorities to investigate instances of discrimination and collectively tackle this issue."
Twitter also released a statement, saying: "Racist behaviour has no place on our service and when we identify accounts that violate any of the Twitter Rules, we take enforcement action.
"We have proactively engaged and continue to collaborate with our valued partners in football to identify ways to tackle this issue collectively and will continue to play our part in curbing this unacceptable behaviour - both online and offline."