Istomin stuns Hewitt with 'never-before-seen' winner

Denis Istomin has left commentators in awe with an incredible winner against Lleyton Hewitt and Sam Groth.

The Uzbek and Mikhail Kukushkin lost 6-3, 6-3 to the Aussies on Thursday, but Istomin produced some absolute magic.

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Istomin was forced way off court by a Groth volley, but managed to uncork an amazing backhand that hit off the net post and landed in.

Hewitt was left completely stunned as the ball went sailing past him, and commentators couldn't believe what they'd seen.

"That's a winner!" John Fitzgerald exclaimed.

"I have never ever seen that."

Groth was so stunned he had to question the umpire whether or not it was actually allowed.

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