He lost the second set from a break up and then won the second from a break down before ending the evening very much on top against the 15th seed from Serbia.

All eyes were on Murray’s right ankle after he rolled it during the second set of his third-round win over Michael Berrer and finished the match virtually on one leg.

The Scot had declined to give any updates on his condition in the 48 hours between matches but still looked very cautious with his movement in a gentle practice this lunchtime.

Berrer had made Murray’s life easy by letting his sympathy for the fourth seed’s plight affect his game but Troicki, who himself had been suffering with food poisoning, was never likely to follow suit.

The early signs were certainly not good from the fourth seed’s perspective as, barely able to run from side to side, he lost five games in a row.

The only question seemed to be how long Murray would continue for but he avoided the dreaded bagel by retrieving one break of serve and slowly the momentum began to change.

His serve had more bite and he was having more success going for big shots. It was not enough to prevent Troicki taking the first set – although he did have points for 5-5 – but there was hope where to start with there certainly had not been.

Murray was still not moving as well as he can but competitive instinct seemed to have overridden any fear of really testing the ankle.

Troicki had never taken a set off Murray in three previous meetings but he has been a different player since helping Serbia win the Davis Cup last year.

Murray needed two big serves to save break points in the third game of the second set, and two terrific forehands then gave the Scot a chance at 3-2, which he took with a third winner.

He immediately gave the break back, though, netting a drop shot on Troicki’s third break point, and he then missed two chances for a third successive game against the serve.

Holding serve was proving extremely difficult for both men, and it was Troicki who gained a second break in quick succession when another Murray drop shot backfired.

That left the 15th seed serving for the set, and, although a double-fault on his second set point betrayed nerves, he took it with a big serve.

Losing that set really seemed to have deflated Murray and his body language was anything but positive at the start of the third. Another break for Troicki in the third game seemed to spell the beginning of the end but the fourth seed dug deep and responded in kind.

Murray was looking much more like his usual self now and in the eighth game he upped his level decisively, hitting a couple of beautiful angled winners and then clinching the break with a crunching forehand.

That left him serving for the set and this time there was no real drama, with the Scot taking it on his third opportunity with a huge serve down the middle.

With the clock ticking past 9pm, there was only time for one more set at best, so it was imperative Murray did not get sloppy at the start of the fourth.

Instead it was Troicki, who was now looking extremely weary, that blinked first, trying and failing to live with Murray’s weight of shot as the Scot broke through to lead 3-2.

Murray then took his second break point with a forehand cross-court winner, giving him the chance to serve out the set, which he managed comfortably to level proceedings after two hours and 52 minutes.