By the time he makes his ring-walk into an O2 Arena filled with fans both supporting and praying for him, Kell Brook will have had a lot of time to think about his date with destiny.
Sixty-four days, to be exact. A lot of time to consider the implications for his career, to decide if moving up 13lbs is the right decision. And a lot of time to think about Gennady Gennadyevich Golovkin, too.
Which must be a pretty formidable prospect. The Kazakh superstar, known ubiquitously as GGG, is probably the most fearsome fighter on the planet right now and Brook is bulking up to play him at his own game.
Despite appearing more comfortable at 160lbs than 147, bookmakers have all but written off Brook’s chances and the underdog retweeted an online poll earlier in the week which saw 88 per cent of fans back Golovkin.
But boxing doesn’t take place on Twitter, or down the local Paddy Power. Success doesn’t even, to some extent, fully happen in the ring on the night; it’s forged in gyms and early-morning training runs, sacrifices in personal life and sheer hunger.
Golovkin has the obvious tools to do serious damage, but Brook is no sacrificial patsy and whatever the outcome on Saturday, he will leave the O2 with the respect of the boxing world at the very least.
Boxing has been good to the 30-year-old, who grew up in a council house in Shirecliffe and now lives comfortably in Ecclesall with partner Lindsey and their two daughters.
He often remembers being taken to Toby Carvery on Ecclesall Road as a youngster, and telling himself he’d live around there one day, with “these big houses with high walls and cameras”.
But there’s rarely glory without sacrifice in any story, and Brook’s fights haven’t been limited to the ring. His mum, Julie, gave birth to him aged just 20 and Brook’s biological father left them both soon afterwards, before meeting Terry - the man Brook now calls Dad - just over a year later.
He grew up in one of the more deprived areas of Sheffield and remembers spending hours in the famous Ingle Gym at Wincobank, while friends from Herries School lined the streets of Southey and Shirecliffe until late, with no purpose.
“I would say that boxing saved my life,” he admitted to me once.
“I was one of those naughty kids growing up in a naughty neighbourhood and, looking back on the kids I grew up with at school, a lot of them are still involved with that bad life. Some of them are in prison, and a couple are dead.
“Without boxing, I would have easily got involved with that kind of thing, too, because that’s all the kids around that area know.”
Now, Brook knows so much more. But it almost all slipped away from him one night in September 2014, when he was stabbed on holiday in Tenerife and almost bled to death.
I would say that boxing saved my life,. I was one of those naughty kids growing up in a naughty neighbourhood and, looking back on the kids I grew up with at school, a lot of them are still involved with that bad life. Some of them are in prison, and a couple are dead.Kell Brook on boxing
Two weeks earlier, he had become champion of the world by beating Shawn Porter in California.
“I had no way of knowing if I would walk again,” he remembers, in an interview with The Guardian.
“It was a rollercoaster. It was mad. I needed my family around me to get through that dark time. It’s definitely changed me because, coming out of hospital, it felt like a new world. I felt the breeze and heard the birds singing. I saw the sand and I was thinking: ‘These small things in life are so precious.’
“It’s changed how I look at life, how I look at my kids. It had a big effect on me – because I was close to death.”
But he’s back now. And as a man who’s made a habit of succeeding against the odds, don’t rush to back against him this weekend - he’s come too far to just wilt in the heat of battle.