Murray came into the match having dropped only 32 games at Wimbledon, tied with Roger Federer for the fewest of any quarterfinalist. It was Murray's best start here through four matches. That's what made Murray's demise in the first set so surprising. It was so sudden it almost didn't register. He looked tentative and cautious, almost listless, like Murray circa 2010. His body language, so positive recently, reverted to the slumping, eye-rolling, surly Scot from early in his career.
In a span of 25 minutes, Dimitrov -- aggressive, moving exceptionally well and serving flawlessly -- won 6 of 7 games and 26 of 38 points. That ended a run of 18 consecutive set wins here for Murray. The look on coach Amelie Mauresmo's face in the Murray box went well beyond mere concern.
In the seventh game of the second set, Murray played another uncharacteristically loose game. At deuce, he stroked a backhand that drifted well wide and followed that with a nonchalant backhand that was long. Dimitrov, who converted his third break point in four opportunities, took a 4-3 lead.
Murray, in his first flash of positivity, broke right back when a suddenly nervy Dimitrov missed three straight backhands. At 5-all, Murray dug himself a 15-40 hole but escaped with three big serves, the last a 130 mph ace, his fastest serve to that point.
But in the second-set tiebreaker, Dimitrov's sublime skill surfaced. At 4-all he hit a lovely one-handed backhand pass. At 5-4 he hit a delicate backhand drop volley that drew a gasp from the crowd. Another backhand volley gave him the second set, and suddenly Great Britain's favorite son looked like the crisp, brown grass along the Centre Court baseline.
They had hummed along into the sixth game of the third set when Murray made another startling donation. A casual backhand and a horrific double fault -- a good foot wide -- gave Dimitrov a 4-2 lead, which he wasted no time consolidating.
"The only thing I can say is I have two more matches to play," said Dimitrov, humbled by his achievement. "I just need to stay on course."
Murray's victory here a year ago ended a 77-year drought for British men. Afterward, he said the pressure to repeat did not contribute to the loss to Dimitrov.
"To be honest," Murray said, "I handled the pressure fine. Today was a bad day from my side. I made many mistakes. I don't feel like it had any bearing on the outcome of the tournament.
"The younger guys are becoming more mature and improving all the time. I need to take some improvements to my game."