Defending champion Andy Murray appeared hampered by injury as he was knocked out of Wimbledon in the quarter-finals by Sam Querrey on Centre Court.
Querrey, 29, won 3-6 6-4 6-7 (4-7) 6-1 6-1 to become the first American man to reach a Grand Slam semi-final since Andy Roddick at Wimbledon in 2009.
Murray, 30, led by a set and a break but the Briton lost 12 of the last 14 games as he struggled physically.
The defeat means Novak Djokovic could overtake Murray as world number one.
Second seed Djokovic, who plays Tomas Berdych later on Wednesday, needs to win the title to return to the top of the rankings.
Murray looked on course for an eighth win in nine matches against Querrey when he led by a set and a break, but less than two hours later he was out, after the American fired down his 27th ace.
Querrey took his chance superbly, hitting 70 winners, 30 of them from the net as he attacked at every opportunity.
For Murray, it appeared that the hip injury that disrupted his build-up to Wimbledon had finally caught up with him.
After breaking serve to lead 4-3 in the second set, letting out a loud “come on!”, Murray dropped serve twice in a row, his opponent firing a brilliant backhand to clinch the set.
Any thought that it was a momentary lapse from the champion disappeared when Murray was broken again serving for the third set, but he took the tie-break on his fourth set point and seemingly regained control.
In fact, it was Querrey who took command as Murray appeared underpowered and unable to move freely.
The Scot won just nine points on serve in each of the fourth and fifth sets, with an average serve speed down at just 108mph, allowing Querrey to tee off on the return.
The American played a magnificent point at the net to break for the eighth time, serving out the match after two hours and 41 minutes.
Querrey will now face seventh seed Marin Cilic in the semi-final after the Croat beat Gilles Muller in five sets.
Muller – who beat Rafael Nadal in just under five hours on Monday – took the first set but former US Open champion Cilic came through to win 3-6 7-6 (8-6) 7-5 5-7 6-1.
‘I gave everything I had’
Murray was struggling with a hip injury in the build-up to Wimbledon, pulling out of two exhibition matches and missing three days of practice before his opening match.
But he would not tell the post-match news conference exactly what his injury was, only that he regretted a missed opportunity to add to his two Wimbledon titles.
He said: “Throughout the tournament I’ve been a little bit sore but I tried my best, right to the end I gave everything I had, and I’m proud about that but it’s obviously disappointing to lose.
“There was an opportunity there so I’m sad that it’s over.
“Before the tournament it was very short-term solutions because you want to play Wimbledon.
“We were looking at short-term solutions and managed to get through a bunch of matches and did OK.
“Now I’ll sit down with my team and look at the longer term, and come up with a plan for what I have to do next.”
Querrey, the 24th seed, reached his first semi-final at his 42nd Grand Slam – a new record.
He said: “I didn’t start my best but I kept with it, kept swinging away, then really found a groove in the fourth and fifth sets and then everything started falling my way.
“It feels great – this is a dream come true, to be in the semi-finals and to have it at Wimbledon makes it feel more special.”
