A number of racist incidents have marred the weekend's football action across Europe and the UK with Valencia's walk off during their La Liga game at Cadiz highlighting the growing scourge.
In London, Tottenham Hotspur defender Davinson Sanchez was subjected to racial abuse on social media after Sunday's 2-2 draw at Newcastle United.
On Saturday, West Brom's Callum Robinson was sent racist abuse online after his starring role in his side's 5-2 victory at Chelsea.
Albion confirmed the matter had been reported to police.
Rangers forward Kemar Roofe also highlighted disgusting messages sent to him, writing on Instagram: "I wonder if you tag @instagram @europaleague in the comments they will see it and take notice?"
The latest high-profile flashpoint came half an hour into Valencia's match against Cadiz, when players left the field of play after defender Mouctar Diakhaby claimed he was racially insulted by an opponent.
The Spanish club said the team only resumed the game after feeling threatened by the referee with the loss of points.
Frenchman Diakhaby reacted furiously after a clash with Cadiz defender Cala at the Estadio Ramon de Carranza.
After remonstrating with the referee, Diakhaby led Valencia's players off the pitch.
They subsequently decided to return and continue the match about 20 minutes later, although Diakhaby was replaced and watched on from the stands.
"NO TO RACISM. The team have held a meeting and decided to continue the game, in order to fight for the honour of the club, but denounce racism of any kind," Valencia tweeted.
"We offer our complete backing to @Diakhaby_5. The player, who had received a racial insult, requested that his team-mates return to the pitch. WE SUPPORT YOU MOUCTAR."
Diakhaby did not return, with Hugo Guillamon coming on in his place, but Cala remained in the Cadiz line-up and the hosts went on to record a 2-1 victory.
Valencia later released a statement saying the players only went back onto the pitch because of the threat of a sanction for not completing the game and expressed disappointment that it was left to them to take action.
"The events of today should not be repeated ever again on a football pitch. Valencia CF strongly oppose racism in all forms and stands with Diakhaby," the club statement read in part.
"Today is a sad day for our sport. Today was not a loss in a game. It was a loss of respect, a loss of the spirit of football and sport."
Cadiz coach Alvaro Cervera defended his player, saying on cadizcf.com: "It's the first time something like this has happened to us and we did not know how to react.
"There was a lot of confusion, but Cala insists he did not insult him. We're a faithful, honest team and we don't do this kind of stuff. That's what I can say."
Meanbwhile, Sanchez endured a difficult afternoon at St James' Park with a number of sloppy moments, including a poor clearance that led to the Magpies' opener.
The 24-year-old Colombian posted a picture on his Instagram Stories after the match showing a series of monkey emojis that he had been sent, and wrote "Nothing changes" alongside a sleeping emoji.
Spurs offered support to their centre-back in a tweet which read: "We are disgusted by the racist messages received by Davinson Sanchez today and are calling on social media platforms to take action. We stand with you, @daosanchez26, and all those continuing to suffer abuse online."