Britain's Kyle Edmund stunned third seed and world number three Grigor Dimitrov in four sets, 6-4, 3-6, 6-3, 6-4 at the Australian Open, to book his place in the semi-final on Rod Laver Arena at Melbourne Park.
After leading throughout the contest, the 23-year-old Yorkshireman kept his nerve in a tense fourth set, as the number 49th ranked player made it through.
The Briton becomes the sixth British male to reach a Grand slam semi-final in the Open era and will face either Rafael Nadal or Marin Cilic in the last four.
Opening sets shared
In his first Grand slam quarter-final, the Brit wasted no time in stamping his authority on events on Rod Laver and broke the Bulgarian third seed in the opening game. After pushing out to an early 3-1 lead however, Dimitrov took three games on the bounce to nose ahead at 4-3.
As Edmund held to stop the mini rot the following game, the Yorkshireman began to force his power game on his opponent and broke again to 5-4.
Saving two break points of his own as he served out the opener, the Briton then went through the gears as the ace tally ticked over and held his nerve to take the opening set 6-4 in the Victoria sun.
As both men, emblazoned in pink overtones ventured out for the beginning of the second set, the 26-year-old from Haskovo went out to an early advantage and fought back from 0-40 in the third game to push out to a 3-0 lead with sights on leveling the match in double-quick time.
The Briton was still exhibiting the greater power across the court, but Dimitrov was finding his own pace to subdue Edmund, with the latter forcing an increasing number of unforced errors.
Attempting to claw his way back into the set, the Brit pulled the deficit back to 1-3 on his serve as the contest began to ebb in the favour of the world number three who went out again to a three-game lead.
It was then the turn of the third seed to tighten up and made three double faults in the seventh game but held to 5-2 as Edmund let his opponent off the hook, just a game from leveling the match.
Holding serve to 3-5, the man from Beverley asked the question of Dimitrov to serve out for the second set, which he duly obliged -under further pressure at 30-30 - to level the match after an-hour-and 25-minutes.
With the match now down to a best-of-three-set showdown at Melbourne Park, the duo vied for the vital early initiative. With Edmund's game still littered with errors, Dimitrov began to pressure for the early break but the Briton's serve was still bailing him out of trouble.
It was then the Bulgarian's turn to buckle a little but came through to level at 2-2. After both men shared comfortable service games, it was Edmund who struck. Serving at 3-4 down, Dimitrov was taken to 15-40 and after saving one break point, double-faulted once more as Edmund broke.
The Johannesburg-born Brit held his nerve under mounting pressure and at 40-30 served out the third wide to the service court, to stand just a set away from a remarkable place in the last four.
Briton keeps cool in tense finale
Thus far in the match, the advantage of serving first in the set had proved decisive and staring defeat in the face, Dimitrov sought a response that was not immediately forthcoming.
Experience had dug the third seed out of trouble earlier in the tournament but it had yet to surface against the 49th-in-the-world ranked Briton. After the opening games were shared with relative ease by both combatants to two apiece, the Yorkshireman struck in predatory fashion.
There was an air of anticipation as the watching Bulgarian fans began to twitch in the arena and at 30-30, Dimitrov made two unforced errors from the Edmund power return as the Brit broke, which was then countered as the former began to dig deep for inspiration.
The contest was quickly becoming a base-line duel for supremacy as Dimitrov saved a further break point in a tense seventh game exchange, refusing to bow to an untimely exit. Edmund leveled at 4-4 and pounced.
At 15-30, the Bulgarian hit a backhand return which went millimetres wide of the service line - after the call was challenged. Edmund lofted a return deep onto the base-line at 30-40, as Dimitrov could only smash into the net cord.
The Briton, serving for the match was visibly nervous and fighting back from 0-15 and 15-30 steeled himself to serve an ace to set up match point. On his moment of destiny, Edmund forced Dimitrov wide on numerous occasions.
Dimitrov whipped a forehand which was initially called long. Hawk-eye was called, as the Brit waited in agony. To his relief - and ecstacy - the call was good and Edmund had knocked out the third seed to book his place in the Australian Open semi-finals.