Andy Murray survived a stern examination of his world number one credentials from Fernando Verdasco to reach the third round of the BNP Paribas Masters.
Murray needs to at least reach the final in Paris to stand a chance of overhauling Novak Djokovic on Monday and becoming the first British player ever to be ranked number one in singles.
That looked highly unlikely when a weary Murray faced two break points at 5-5 in the deciding set against an inspired opponent, but the Scot held on and ground out a 6-3 6-7 (5/7) 7-5 victory.
It was a 16th win in a row for the 29-year-old, who is bidding for a fourth straight title after winning trophies in Beijing, Shanghai and Vienna last week.
As if that was not enough cause for optimism, Murray had beaten Verdasco in 11 of their 12 previous meetings.
The Spaniard's only win came at the 2009 Australian Open but the big-hitting Spaniard has often given Murray trouble, not least when he led by two sets to love in the quarter-finals at Wimbledon three years ago.
Murray fought back for one of his most memorable SW19 wins and went on to win the title.
If this victory is to lead to another landmark moment, he will remember this match as one that could so easily have got away.
The first set was plain sailing but Verdasco, whose forehand can be one of the biggest weapons in the game, stepped things up impressively in the second.
He broke Murray for the first time in the fourth game with a crisp winner and then, after the second seed had pegged him back, moved ahead again for 5-3.
Verdasco failed to serve it out but was not to be denied in the tie-break, taking a 6-2 lead and finally converting on his fourth set point when Murray netted a backhand
Murray looked to have made a key breakthrough when he opened up a 2-0 lead in the decider but back came Verdasco.
Murray was beginning to look understandably tired and was on the back foot for much of the third set.
The crunch moment came when Verdasco moved to 15-40 at 5-5 but he could not convert either chance, being denied by a net cord on the second.
And the Spaniard, who has a reputation for faltering at the last, then played a dreadful game to hand Murray the victory.
The Wimbledon champion now faces a quick turnaround before taking on 13th-seeded Frenchman Lucas Pouille on Thursday.
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