Murray has repeatedly said he is not about to retire after a horror run of form but the fierce competitor inside him will not be able to put up with too many more defeats like this, at one point appearing to shout to his team: "this game is not for me any more."

Murray, whose first-round win over Alexandre Muller on Tuesday was his first victory since October, was beaten 7-6 (6) 6-7 (3) 7-6 (4) in over three hours by the 18-year-old.

The Scot will have nightmares about a volley he missed on set point in the first-set tiebreak and then the way he lost the final-set tiebreak after fighting back will frustrate him.

Murray will consider Mensik an opponent he should not be losing to, especially has he had already won eight games on the ATP Tour by the time the Czech was born.

But he handed the advantage to his opponent in the third game of the first set when two successive failed drop shots allowed the Czech to break serve.

Mensik, just 18, had played some scintillating tennis in the first set but lost his nerve when he tried to serve it out at 5-4, with Murray breaking back.

It went to a tiebreak and Murray will be going to bed thinking of the simple volley he missed when he had two set points.

Instead of putting it into an empty court he dumped it into the net and went on to lose the next four points and the set.

The second set went on serve, with Murray fashioning a break point at 5-5 which would have left him serving it out.

However, he hit a short ball into the net and vented his frustration to his team.

To his credit, he recovered to send the second set to a tiebreak and this time he did not mess about to level up at one set all.

Murray appeared to have thrown it away as his level dipped at the start of the third and Mensik broke twice to lead 5-2 on the decider.

But the 37-year-old, who is playing with a metal hip, unlocked prime Murray mode and won four successive games, including two where Mensik was serving the match.

The youngster stopped the rot to send it to a deciding tiebreak and picked himself up off the canvas to claim a memorable scalp.

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Finished Australia in India Test Series