RYAN GARCIA threw a left hook so fast the camera barely caught the punch - in a warning to Gervonta Davis.
Garcia knocked out Javier Fortuna in six impressive rounds with the fight ending on a stunning combination.
The American landed a perfect one-two and finished it off with a left hook which floored Fortuna and closed out the bout.
In footage captured from inside the Los Angeles' CryptoArena it shows the exact moment Garcia connects with his left hand.
But the punch was so fast the naked eye can barley see it.
Garcia captioned the post: "Gervonta come out, come out, wherever you are."
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The unbeaten star, 23, has made it clear Davis, 27, is his No1 target to fight next.
But he wants the fight in the 140lb light-welterweight division opposed to at 135lb as lightweights.
Garcia said: “I felt way better. I’m not going back to 135 for nothing, but I want Tank next.
“I’m never afraid, I have a spirit of competition. You’re going to see that when I fight Tank.”
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Garcia has lined up former unified champion Teofimo Lopez, 24, as an alternative option.
He said: “If that fight, for some reason, doesn’t happen, which I don’t see that happening, but if it doesn’t happen, then I wanna fight Teofimo Lopez at 140.”
Davis cryptically responded online: "See y’all the end of the year."