Romelu Lukaku baffled fans when he walked out onto the Old Trafford pitch with the name 'Crystal' written on the back of his Manchester United shirt.
Red Devils supporters took to social media to try and find the answer, after Sky Sports cameras captured the Belgian sporting the name on his jersey.
Cameras only caught the back of Lukaku's shirt, making it seem like he was the only one wearing a different name, but in fact every Man United player wore another name on their shirt.
So what exactly are they all playing at? We're glad you asked.
Manchester United sponsors Chevrolet has an initiative called 'Beautiful Possibilities', which helps provide children with a stable environment to play football.
And one thing it encourages the Manchester United first team to do is wear the name of the mascot they walk out onto the pitch with on the back of their shirt.
The Red Devils stars then remove the shirts moments before kick-off and give them to the young United supporters before putting on their official jerseys.
This means that the young fans go home with a tangible memento from their day in the form of a shirt worn by their favourite player.
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