Milos Raonic's explosive serve is so scary it may soon come stamped with a Surgeon General's warning.
Watch Raonic, who doesn't even appear to be swinging that hard, hit the head right off the racquet while practicing serves.
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That's right, he decapitates the racquet hitting a practice serve.
Listen carefully and you'll hear Raonic's coach, Riccardo Piatti, say "Be careful, huh" before his charge swings perhaps knowing the devastation the Canadan can cause.
This could be slightly intimidating for returners.
Now we know why Milos' hair is so scared to move.