A portrait displayed at the National Gallery has puzzled art enthusiasts after a mum and daughter spotted what appears to be a Nike trainer.
Portrait of a Boy, painted by Dutch Master Ferdinand Bol in the 17th century, features an eight-year-old boy standing in the foreground holding a goblet.
The youngster is wearing a black jacket and cape, a white shirt with ruffled sleeves, auburn socks and black boots, in keeping with the time period.
However, upon closer inspection, it appears that the boy's shoes are emblazoned with a white tick uncannily similar to the famous Nike 'tick' logo.
The fact that Nike was founded hundreds of years after the portrait was painted has led some to suggest that the artwork is proof that time travel exists.
Fiona Foskett, 57, spotted the unusual detail during a visit to the London gallery with her daughter, Holly, 23.
She told The Sun: "I said to my daughter, 'Hold on, is he wearing a pair of Nike trainers?'
"Looking at the age, he must have got his hands on the first pair of Nike trainers ever made. Or is he actually a time traveller?"
A spokesman from the National Gallery told the publication: "We are delighted that this picture has been such a hit with our visitors.
"It resonated with followers when we put out a Tweet asking people to see if they could spot a more 'modern' detail by taking a closer look at the shoes of the eight-year-old boy in the portrait."
Believe it or not, this isn't the first time that modern items have been spotted in antique artwork.
Last month, art fans spotted what appeared to be an iPhone in a painting from 150 years ago.
The Expected One, painted by Ferdinand George Waldmüller in the 1860s, features a woman who looks like she is completely mesmerised by a rectangular item she is clutching in her palms.
However, speculation was quickly put to rest when it was revealed that the image actually shows the woman focusing deeply on her hymn book.
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