Andy Murray's competitive return to action will conclude with a scarcely believable appearance in the final at Queen's Club after partner Feliciano Lopez went above and beyond the call of duty.
Five months after undergoing career-saving hip surgery Murray, supposedly taking baby steps on the comeback trail, is on the verge of a title at the very first attempt.
But it was Spaniard Lopez who put in the superhuman effort, spending just under five hours on court.
The 37-year-old initially took a break from his role as Murray's support act to reach the singles final after winning a three-setter against teenage sensation Felix Augur-Aliassime.
Lopez, champion here two years ago, had a 12-minute breather between that 6-7 (3) 6-3 6-4 victory before he and Murray resumed their quarter-final, suspended due to fading light on Friday night, against British duo Dan Evans and Ken Skupski.
Just 14 minutes, three games and a tie-break later, Murray and Lopez had secured their place in the semi-final, and then sat waiting courtside for their next opponents, reigning Fever-Tree champions Henri Kontinen and John Peers.
Kontinen and Peers presented a big step up in class but somehow Murray and Lopez triumphed again, sharing the first two sets before staggering over the line in a match tie-break, 10-7.
Having taken to the court for his singles match at 4pm, an exhausted Lopez said at 8.55pm: "It's crazy. If someone had told me a week ago, I would say you're crazy.
"To be here again in the finals in both singles and doubles, it's tough to believe, no?"
Murray, who revealed he had a chat with former Manchester United manager Jose Mourinho before his time on court, added: "He did brilliant, really. Not just in the way he played but in the way he carried himself at the end of the match and stuff. Big energy, getting pumped.
"It was cool for me to see that, you know? He's been on the tour for, like, 20 years and I appreciate that he's got a big final in singles to play tomorrow and it's getting dark and late for the second day in a row.
"But he did really, really well. Yeah, it was a great, great effort from him."
Murray and Lopez will meet Rajeev Ram and Britain's Joe Salisbury in the final on Sunday.
Salisbury, 27, who grew up just down the road in Putney, said: "I have won two ATP 500 titles before but I think this would be extra, extra special and sort of even bigger because I'm playing basically at home."
Before that, however, Lopez will face Gilles Simon in the singles final.
Simon himself has been something of a marathon man this week and he came through another gruelling three-setter against Daniil Medvedev.
The Frenchman has gone the distance in all of his four matches, including the longest in the history of Queen's Club against Nicolas Mahut, a three hour 20 minute marathon, on Thursday.
"It was hard to recover and this one was tough with long rallies," said Simon.
"We practice together and we knew it would be long. It was a tough match.
"It's hard for me to hit through him but I was feeling the ball great today, the feeling is great in the shot, even if it's not in the legs!"
Meanwhile, Murray's proposed mixed doubles stint at Wimbledon is unlikely to feature Maria Sharapova despite her online offer.
"I think we played once together before and I don't remember us playing particularly well together," he said.
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