Everton have removed a T-shirt from their online store after eagle-eyed supporters noticed that the main image was in fact of rival city club Liverpool's Kop.
The 'Everton Royal Crowd T-Shirt' was swiftly taken off sale after the embarrassing gaffe was noticed.
Using the image of the Liverpool fans, Everton had mixed the photo with a blue background before adding the club's logo on top.
Everton have removed a T-shirt from their online store after using an image of Liverpool's Kop - an eagle-eyed fan tweeted this composite image highlighting the error
However, it is obvious that it is in fact the Kop with the open windows at the back of the stand and a Liverpool flag featured in the picture.
Everton declined to comment but are understood to be furious at the incident, for which an external company was responsible, and acted to swiftly to remove the item.
The image was taken during a First Division match between Bill Shankly's Liverpool and Don Revie's Leeds on April 28, 1969.
It was a rather dull 0-0 draw at Anfield but a point was enough to see Leeds clinch the title in front of 53,750 fans.
The image was from a First Division match between Liverpool and Leeds on April 28, 1969
A Liverpool flag can be seen while the open windows at the back of the stand show it is the Kop
The page where the T-shirt used to be on sale no longer exists on the Everton online store
The error is sure to add a bit more spice to the Merseyside derby in the third-round of the FA Cup next Friday.
Liverpool welcome Everton to Anfield just four weeks after Sam Allardyce's men held them to a 1-1 draw in the Premier League.
Mohamed Salah put Jurgen Klopp's Reds in front before a second-half penalty from Wayne Rooney ensured Everton took a point back across Stanley Park.