The device saves all the data from each hit, namely the animation, path, putter-face angle at impact and throughout the stroke, angle of attack, tempo, impact speed and swing path distance -- in other words, more information than most players would know what to do with.

ENGADGET: 3BaysGSA Putt: a Bluetooth golf gadget that puts eyes in your putter (hands on)

Yet there he was Sunday evening and Monday morning in Melbourne, matching Djokovic stroke for stroke, angle for angle, absurd winner for absurd winner.

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During the swims, the researchers measured the volunteers' oxygen consumption, rectal temperature, swim speed and angle, and stroke rate and length.

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Following each flail, a clear graphic representation of your stroke path along with several key stats will display on your device: the critical putter-face angle at impact and tempo, among others.

ENGADGET: 3BaysGSA Putt: a Bluetooth golf gadget that puts eyes in your putter (hands on)