Boxer gets hit with a brutal left hook out of nowhere, goes down, and doesn't move

This is as frightening as it gets.

This is one of the scariest sites you'll ever seen in a boxing ring.

Middleweights David Lemieux and Curtis "The Cerebral Assassin" Stevens squared off in HBO's Boxing After Dark series, and really, I was afraid for Stevens.

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That's because, in the third round of a scheduled 10-round bout, Lemieux throw a short, quick and devasting left hook that caught Stevens flush on the chin.

And Stevens was out before he hit the mat. And when he went down, he didn't move. Didn't even flinch. Check it out.

Luckily, Stevens is OK.

Sports Illustrated wondered if the bout would be the Fight of the Year:

Instead, we got what is clearly the knockout of the year, so far.

Lemieux improved to 37-3,with 33 KO; Stevens fell to  29-6, 21K