For Jessica Ennis, the time is nigh. Come 10.05am today, Olympic gold will be on the line for the Great British hope o f track and field as she sets out in event one of the heptathlon, the 100m hurdles.
The Sheffield woman starts as the favourite and the world No 1 but, in a closely-matched field, she knows it could all come down to a dramatic denouement in the final event at around 8.35pm tomorrow, the 800m.
Everything points towards a two-lap scrap for the gold between the diminutive Briton and Tatyana Chernova, the towering Russian who relieved her of the World Championship title in Daegu last summer.
"God, that makes me so nervous," Ennis says, contemplating the scenario in the calm before the storm. "I have put a lot of hard work into the 800m and done some really horrible sessions, so I would tell myself I have put all the hard work in – and if it does come down to it, I could… take her down."
The last three words are delivered with the mock intonation of a female assassin in a Hollywood action-thriller. As soon as they pass her lips, Ennis realises they might not be taken in jest. "Don't quote me," she says, laughing, and in vain.
The message is already on half a dozen tape recorders. "Damn you," she says, only half-mockingly this time. "It's going to be everywhere."
It is good to see Ennis on such good form. For three years now, ever since she won the World Championship title in Berlin in August 2009, the pressure of home Olympic expectation has been building on her shoulders.
Every day and everywhere that Ennis has ventured, the Great British public have stopped her and implored: "Win us that gold medal." She features on the front cover of the latest edition of Time magazine. Back home, in Sheffield city centre, there is an 80ft poster of the 5ft 5in pride of the Steel City.
There has been no escape for Ennis – even after a hard day's training, when she has been attempting to relax in front of the telly with her fiancé, Andy Hill. "When that BP advert comes on, I think, 'Oh no, not this again.' And Andy pauses it and we have a laugh about it.
"That lessens the importance of it all and makes it easier. But it's hard to get away from it. Every advert on telly is about the Olympics. It's been on Corrie. And there's school sports days… It's everywhere."
And everywhere, the vast majority of people have been quick to hang the gold medal around the neck of the 26-year-old psychology graduate. Only those who follow track and field appear to appreciate that it is a far from foregone conclusion – that Chernova and the defending Olympic champion Nataliya Dobrynska of Ukraine are serious threats to Ennis, and that one big slip in any one of the seven events could cost gold.
"It kind of washes over me now," Ennis says. "I know how hard it is going to be and what it is going to take. I know that it won't be easy at all.
"But I think people mean it in a nice way. They are saying, 'You winning that gold will be great,' so it is a nice kind of support. I think it is a good thing to have home support, to have the crowd behind you. The crowd getting crazy – I know this sounds a bit cheesy – but it does carry you along. It helps a lot to have that support. I love it."
Ennis has every reason to savour her London Olympic experience. This will be her debut in the greatest sporting show on earth. She missed the Beijing Olympics four years ago after suffering a triple stress fracture of the foot. "I wasn't going to watch the Games in 2008," she says, "but you couldn't really escape it. So I did watch a lot of it, and obviously the heptathlon.
"I wanted to see what happened, for it to be over, and to move on. It was hard to watch, because I did want to be there. Now that I am going to be at an Olympic Games, I shall definitely be nervous, like I am before every major championships. We only do two heptathlons a year, so I am always nervous going into them.
"I know it is on a much bigger scale this time but I am trying not to think about that. I am looking at it as still a heptathlon, which I have done many times: the same rivals, in a stadium."
In the tranquil Alpine setting of the Mosele Stadion in the Hypo-Meeting heptathlon at Götzis in Austria in May, Ennis was too good for her rivals, beating Chernova by 132 points and breaking Denise Lewis's 12-year-old British heptathlon record with a score of 6,906 points. Dobrynska finished down in ninth place, understandably out of sorts just two months after the tragic death of her husband-cum-coach.
"That must have had a huge effect on Nataliya's form in Götzis," Ennis says. "I imagine she is going to be a lot stronger now. She has had more than enough time to get some good work in. Everybody is going to be in great shape. It is never easy.
"I do feel very good, to be honest. I am very happy with the year so far, with what I have done.
"I think Götzis was important. Breaking the British record did give me a lot of confidence. But, at the same time I know that Dobrynska may be different when it comes to the Games, and Chernova. You just don't know."
We will know over the course of the next two days. But then what? Has the big British hope given a thought to life beyond the heptathlon finish line?
"It is weird," Ennis ponders. "It does feel like the world is going to end after the Olympics. It is such a big build-up, and a lot of things will change because it is the pinnacle and people will retire, and younger athletes will come through. For now I am thinking just about those two days and getting that gold.
"I'll be having a holiday, and after that I am not sure. I know I want to carry on. I don't want to retire just yet. You have to make the most of your athletics career. I know I want a big break but I know it will get to the point where I will get a bit twitchy and want to come training again."
Jessica's route to glory...
Ennis is a world-class hurdler. She beat British record holder Tiffany Porter at the trials, and has beaten former world indoor champion Lolo Jones several times. It is a perfect vehicle for her natural speed and the power she has in her quadriceps. 9/10
Ennis is joint holder of the British record in the high jump, with 1.95m. She has struggled to find consistency in the event in the past two years, however. She has tremendous natural spring in her feet and calves and can jump almost a foot above her own height. 8
Despite her slender weight, Ennis has an excellent power to weight ratio. The shot is not one of her strongest suits but she has developed a smooth technique and found a steady level of consistency. The oblique muscles that drive the shot are not her most prominent but they do the job. 6
Another strong suit for Ennis. At Götzis in May she broke through the 23sec barrier, improving her lifetime best by 0.23sec to a brilliant 22.88sec. She is powered by her leg muscles (quadriceps, hamstrings and calves) and her hips and the gluteus maximus muscles of the buttocks. 8
Ennis equalled her personal best in Götzis, with a 6.51m effort, but she has struggled to hit the board this summer and will have only three attempts to get it right tomorrow. The most important muscle here is the calf in the take-off leg. 6
Having messed up in the javelin at the World Championships in Daegu last year, Ennis has worked long and hard on her technique this winter. She has found a consistent groove, throwing a lifetime best of 47.11m in Götzis. The shoulder and the triceps muscle are crucial to delivery. 6
Ennis has a best of 2min 07.81sec but is capable of going faster if need be – which she might have to if she is to beat Tatyana Chernova and Nataliya Dobrynska. The leg muscles are the most important – quadriceps, hamstrings and calves. 7
... and her rivals
The 24-year-old Russian is reigning world champion and has steadily improved since winning Olympic bronze in 2008. Chernova edges Ennis in the 800m – the definitive final event – and is significantly stronger in the javelin and long jump, where she will outclass most of the field.
The powerful Ukrainian, 30, won Olympic gold in Beijing and has enjoyed something of a resurgence this year after a disappointing 2011. She traditionally excels in the throwing events but is behind Ennis and Chernova in the track and field categories.