Andy Murray survived match point before recording a 4-6 7-6 7-5 victory Grigor Dimitrov in a dramatic Cincinnati Masters third-round clash.
After looking second-best for much of the early stages, Murray appeared on course for victory following an impressive response to falling behind, but it was Dimitrov who claimed control in the decider before wasting match point to ensure that it was the Brit celebrating a memorable triumph.
Dimitrov set out his stall early on as the Bulgarian broke his Scottish counterpart in the very first game to move 1-0 ahead.
From there, each and every game went with serve as the early break proved pivotal in helping the world number 14 to draw first blood.
The prospect of an upset improved considerably when Dimitrov won four of the first five games in the second set to establish a commanding 4-1 lead.
Murray - a two-time champion in Cincinnati - broke straight back and then held serve to reduce the deficit to one game and retain his hope of a first title since 2011.
The 2013 US Open champion had to draw on his famous grit as he eventually edged out Dimitrov against the serve in an arduous eighth game to level up the set, before cruising into a 5-4 lead.
Dimitrov showed impressive resilience to ensure that a tie-break was needed, and after both players traded mini-breaks, it was Murray who moved ahead of the Bulgarian before a double break handed the set to the third seed.
The momentum appeared to be in Murray's favour, and the escape act looked set to continue when he secured a break of serve in the opening game of the decider.
However, the drama was far from over as Dimitrov pulled level, before a double fault from Murray in the sixth game gifted him the advantage after he had survived two break points on his own serve.
As was the case in the second set, Dimitrov did not looked comfortable with the lead, but he displayed his resilience to save one more break point.
A thrilling match appeared to be nearing its conclusion until Murray produced another stunning fightback to break back with Dimitrov serving for the match.
Predictably, another dramatic game followed as Murray offered his rival match point, but Dimitrov missed the chance before playing at a ball which appeared to be going wide to let the two-time champion off the hook.
The latest setback proved to be too much to recover from as Dimitrov was broken for the second service game in a row, and Murray capitalised to finally come through the toughest of challenges.