Premier League teams have blundered again by choosing kits that make the two teams indistinguishable to up to 100,000 TV viewers.
The latest mismatch came between Sheffield United and Chelsea, when the teams met at Bramall Lane on Sunday, in a game televised on Sky.
Chelsea ran out 2-1 winners, but colour-blind fans were the losers, since the red and white of the Blades’ shirts merged with the 'arctic blue' of Chelsea's second strip.
Viewers immediately took to Twitter to complain.
'Someone with a bigger brain has got to explain how this is easier to see than Chelsea playing in their home BLUE kit?' said LoftForWords.
'What a ridiculous, unnecessary kit choice from Chelsea tonight #SHUCHE,' posted The Kit Mon.
'I turned it on, saw 20 matching shirts and simply turned it off again...' said Mark Blondal.
Fans were annoyed that Chelsea's traditional blue home kit would have been the perfect choice for the game.
'Well done Chelsea FC,' said Johnny Wogan. 'You really needed your almost white away kit for this fixture. The traditional blue would obviously have clashed with the mostly white shirts of Sheffield United.'
Figures from the charity, Colour Blind Awareness suggest that almost 100,000 people watching the top-tier clash would have suffered from colour blindness and struggled to distinguish the two sides.
It is the fifth time this season that two Premier League sides have met and produced a 'colour-blind kit clash', despite UEFA, the FA and the Premier League producing volumes of guidance on the issue and clubs knowing this is a problem.
The FA has produced a video to highlight the difficulty colour blind people have distinguishing the two colours.
And the Premier League has developed a 'colour blind friendly flag’ which identifies the best kit combinations for people who are colour blind and uses a 'bespoke online software tool' to test whether strips should be worn together.
Clubs submit their kit choices to the league ahead of matches for approval. However, it is the clubs that make the final decision.
'There is software that should have highlighted this,' said Kathryn Albany-Ward, the chief executive of Colour Blind Awareness.
'When the Premier League receive the kit choices from the clubs they run the software and highlight if it could be a kit clash. Then it's up to the clubs to decide.
'There must be a reason Chelsea are playing in the away kit. Perhaps it is a sponsor's agreement?
'They have decided they know better. That is my inteprestation from what has hapened before. It is the club's decision to override the Premier League administrators, if that's what they want to do.'
In this case, the shirts and socks became indistiguishable for colour blind viewers, according to Albany-Ward.
Sheffield United's tops are white on the back and because the red stripes on the front merge with the green of the grass, it looks white from the front too, to a colour blind person. Chelsea's pale blue shirt also looked white to people with colour vision deficiency.
Meanwhile, the Blades' red socks merge with the grass and become indistiguishable from Chelsea's socks.
'They know about this issue,' added Albany-Ward. 'They know it's disability discrimination and they are not doing enough about it.'
It's not the first time a Premier League game has been rendered un-watchable for people who are colour blind because of a kit clash.
The most-watched Premier League game in British history between Liverpool and Manchester United was also a disappointment for hundreds of thousands of viewers, on January 17.
Almost five million football fans tuned in to Sky, but an estimated 300,000 of them struggled to tell one team from the other because Manchester United had selected their 'earth green' third strip for the match-up at Anfield, while Liverpool wore their traditional red.
Red and green, particularly in a similar shade, are hard for colour blind people to distinguish. Manchester United said they realised there was a problem and changed the colour of their socks, believing this would be sufficient.
In the event it was not. The mistake was particularly embarrassing because United's star player, Bruno Fernandes, is a colour-blindness amabassador.
With one in 12 men and one in 200 women affected by the condition, almost three million people are colour blind in the UK. However, the effect is exagerrated in football because men are more likely to be watching. UEFA estimates that 65% of fans are male.
Other kit-clashes this season include, Southampton v Manchester United, Sheffield United v Southampton and Liverpool v Crystal Palace.
'It's been happening all season, so many kit clashes and absolutely nothing gets done about it, it's utterly shameful,' @logan67_logan said on Twitter. 'People think colour blindness is a trivial issue, it's not, and these kit clashes are ENTIRELY AVOIDABLE, that's the worst part of it. Blatant Discrimination!!'
And Dave Pearson added on the social media channel: 'Crazy how the Premier League can change the ball to a yellow one to make it easier to see for all but can’t sort out shirt colours.'
And it is not just football. The Rugby Union international between Wales in red and Ireland in green, was also not watchable for many viewers.
'Sunday was not a good day for watching sport on TV, if you are colour blind,' added Albany-Ward.
During the last football season, Colour Blind Awareness identified 11 kit clashes in the Premier League.