Karen Khachanov found himself in a pretty bizarre cap drama as he fell foul of the famously strict Wimbledon rules on attire.
The Russian, who is seeded number 25 at SW19, made his way through the start of his quarter-final clash against Denis Shapovalov without drama.
But then it was brought to the attention of officials somehow that there was too much black on the inside of his baseball cap. Yes, the inside.
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To make it abundantly clear for context, Khachanov's cap was white. But there was apparently too much black inside the cap, so it had to be replaced.
Cue somewhat amusing scenes as the Russian had the cap changed on Court One.
The reaction on social media reflected the views of many inside the court as Khachanov replaced the offending cap to tighten up his white attire.
Shapovalov, the 10th seed, took the opening set 6-4 before Khachanov hit back to take the second 6-3 to level up the match.
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