A couple of months ago, on a sunny morning in Twickenham, George Groves looked ahead to his rematch on Saturday night against Carl Froch with the same quiet amusement and interest he used when describing his plans for that afternoon. Sitting in the garden of a famous old rugby pub, the Cabbage Patch, he smiled when discussing Froch’s attempts to control himself amid Groves’ needling provocations. He then outlined his role at an Easter play to be performed a few hours later at a primary school.

His wife Sophie, “Mrs Groves” to her class, had been working for weeks as she helped her small students prepare for their end-of-term production. The innocence seemed striking when set against a bitter fight between Froch and Groves. This is the kind of ominous contest that can make even a seasoned boxer pause in his loneliest moments. It is a fight with the capacity to force Froch and Groves, two hard but intelligent men, to feel apprehensive when they consider everything they could lose.

Groves is different in public. His ability to remain amiable and smart marks him out as a distinctive presence in boxing’s anarchic world. There also appears to be a contentment at home that contrasts with the unsettled mood of many fighters outside the ring. He celebrated his birthday in late March and our plan to stage the first in a series of interviews the day after he turned 26 was scuppered by Sophie Groves’ thoughtfulness. “So sorry but tomorrow is my birthday and the mrs has made plans for us,” Groves messaged me on 25 March. “That means I’ve got a lot to catch up with on Thursday. I could do Friday at 12pm if that’s ok? Apologies for the late reschedule.”

The polite tone was typical Groves – and so it seemed unsurprising that our Twickenham interview should be followed by a primary school play. “I like to support Sophie,” Groves said. “She’s worked hard on this. It’s just a little weird because I’ll be the only one there that’s not a parent – but I sit at the back.”

Does he get recognised? “The kids know who I am and their parents do a double-take. It can be funny because Sophie hears them say: ‘I saw George Groves on TV last night.’ They won’t say: ‘I saw Mrs Groves’ husband.’”

Groves reconciles these opposing worlds. He manages to blur the sweetness of being the husband to a young teacher, whom he met when they went to nursery school together, with the prickly machinations of the fight game as he strives to get under the skin of a world champion who wants to hurt him badly. “It’s easy because Sophie’s been with me a long time and she allows me to live a normal life.”

It is always more difficult for a fighter’s partner in the agonising buildup to a contest this intense. But Groves was emphatic that his wife would control the worry that must spread inside her. “She’s supremely confident in me. I remember before I fought James DeGale [his first big fight, in May 2011] Sophie said DeGale was terrible and I had to explain that, actually: ‘He’s not bad.’ She kept saying: ‘No, no, he’s terrible.’

“The first time I fought Carl was different. It was more a case of me telling her that Carl was terrible. She took Froch much more seriously but she was like: ‘OK, I’ve heard you going on about this fight for years so … I’m fine.’ When I know what’s going to happen she’s at ease. The bigger the fight, the more comfortable I am. So is everybody else – apart from dad and mum.”

When I first interviewed Groves, early in 2011, he suggested that, in regard to his parents: “I’ve aged them. Dad goes into his shell and he’s very quiet before a fight.”

Three years on, how is his dad coping with the stress of the rematch? Groves laughed softly. “You realise it’s a big fight because I go around to my mum and dad’s place and all they want to talk about is what was said in this or that paper. I say: ‘Gee, Dad, you don’t need to read me that extract from the Fulham Chronicle.’ In his old age he’s getting animated. Maybe it’s the pressure or the fact he’s semi-retired and has too much time to obsess about boxing. He’s a painter and decorator but work dried up and he’s 60 now so I don’t want him climbing up and down building sites any more. I tell him: ‘Don’t worry, Dad, we’ve got it under control.’

“Mum takes it more to heart. I tell her not to worry about me being the bad guy. Before the first fight she said: ‘I’m worried you’re going to get booed.’ I said: ‘Mum, don’t worry – I am going to get booed. But they’ll cheer me at the end.’ I just didn’t expect them to cheer me that much. But she’s the one going back and forth to Sainsbury’s and people stop her and probably want to say: ‘Your son’s a right arrogant prick, isn’t he?’ But everyone is being lovely about me now.”

Groves sipped his water and grinned, as unruffled as he had been for much of a coolly storming display in the first fight. He dropped the champion in the opening round and dominated Froch so convincingly it was a shock when, even though Groves was hurt, the referee stopped the bout prematurely in the ninth. Much had since been made of Froch’s ability, with a psychologist’s help, to control his emotions in a way he once found impossible. But Froch still snapped during a Wembley photoshoot.

“All it took was for me to say: ‘Hold it together, Carl,’” Groves remembered of when Froch, unsettled by a challenger who is 10 years younger, shoved him angrily. “I didn’t say anything about Carl or insult his family. I just asked him to hold it together.”

Groves pointed out that few people know he has a brother and a sister. In contrast, Froch’s brothers, Lee and Wayne, are the champion’s loud companions. Their building business is bolstered by the boxer’s financial clout and after that Wembley shove, Lee Froch confronted Groves. As he headed off to the less-spiteful school play Groves told me he had since received various texts from Lee Froch – and he made clear his dislike for a family without the same low-key attitude as his own.

The weeks pass and it is not always easy to meet Groves for the next interview. His training intensifies and the sheer size of the occasion takes hold the closer we get to a fight that will be watched by 80,000 at Wembley and millions more on pay-per-view. When we talk again, his attention locks on to Froch. “Only Carl knows whether he’s calm or not,” Groves says. “But if he needs to put energy into creating the perception of calm, that’s still wasted energy. I know there’ve been times when he’s felt good and he has done a much better job than before. We had a meeting on Ringside [Sky’s boxing programme] and Behind the Ropes [a documentary series] and he felt very good. But why did he feel good? He might need to double-check I’m not allowing him to feel good.

“The following day we went to a Facebook interview and by the end there were visible sweat rings under his arms. His mouth was dry. So even if he seems to be holding it together, it’s taking so much energy. At Facebook he showed up thinking he had cracked it but very soon he realised he hadn’t. There are many layers to what I bring to the fight both in and outside the ring.”

Groves has enjoyed trying to unsettle Froch through a variety of stunts. He began with a cheesy touch, producing a Rubik’s Cube at the opening press conference and then repeating allusions to the number six and his “Everything for a reason” mantra. “The Rubik’s Cube was a bit of a laugh,” he says. “With these scenarios I like to see what pans out because Carl’s definitely a thinker. He will sit and stew about it and try to understand what it means. And he never will. When it comes to the number six Carl doesn’t even get it when I explain it coldly and clearly. That’s because he’s no longer humble. He’s a self-elected international superstar. It’s dangerous to put yourself on that pedestal.”

The number six is also a reference to the end of the sixth round of their first fight, when Froch sat on his stool and said: “Fuck me.” Froch has claimed it was simply surprised exasperation that he had allowed himself to be tagged so often in that round. Groves shakes his head. “It seems strange he was surprised after six rounds. You’re halfway through a fight by then. He said: ‘Fuck me,’ because he was out of his depth. He has too much respect for Rob McCracken [his trainer] to say: ‘Fuck me, Rob, why didn’t you tell me he was this good? Why aren’t I prepared for this?’”

Froch may have looked ponderous but he proved the depth of his fighting heart to force a stoppage that still rankles with Groves. “When that first bell goes I’m going to take it as the start of round 10 – because that first fight isn’t over.”

In our final interview I ask Groves to describe his mood just days before the fight. “I’m even more excited this time. All the weight problems are gone and you’re in fight zone. You’re fit and ready to hurt people. Sparring has been really good and I’m almost holding back. I don’t need to sharpen the knife any more – otherwise it might break.”

Froch is iron-willed and Groves concedes: “There’s no quit in him. That’s for sure. So it’s not going to be easy. But Carl’s still very insecure. You can’t say that about me. I’m supremely confident and it borders on arrogance. On fight night I feel alive and full of tingles. You feel your blood flow hot but that’s how we like it. We’re mammals, we’re warm-blooded creatures.”

We seem a long way from a sunny day in April but I still ask Groves about the school play. “Yeah, it was OK,” he remembers. “Apparently I told Sophie there wasn’t enough singing. But it was good to be there for her. Sophie and the whole family are here for me. I go past my mum’s on the way to the gym – and I pop in for the loo or a cup of tea. It’s very normal.”

As the fight moves like a juggernaut towards him and Froch, normality is obliterated. It will be a wild night as Groves’ intelligence and composure are tested by Froch’s resolve and malice. There will be no time to think of school plays, Rubik’s Cubes and cups of tea. Will the coolness of Groves, a much more subtle operator than Froch’s self-styled “warrior”, withstand the brutality?

“People look at me and think: ‘He’s completely punching above his weight.’ They say I’m gonna get knocked out or I can’t hit hard. But fighters get in the ring with me and they’re never the same afterwards. Look at DeGale – he’s won fights since I beat him but he’s never been the same. It’s the same with Froch. Everyone will see the repercussions of the last fight in this next fight.”

Does Groves allow himself to visualise the moment of victory? “It’s a really good question. Sometimes I imagine it and I catch myself. Two years ago I was scheduled to fight for a world title and I was thinking of my pay rise and walking around with the belt. I then busted my nose. The fight was off. So you need to appreciate what you’ve got – and wait for what you’ve not quite got. Once I’ve got that world title I’ll never want to lose it. I’ll fight tooth and nail to keep it. But, first, I will win it.”

Week after week the same conviction has flowed through Groves. Saturday night will be a new experience, far beyond the routines of daily life, but he seems primed for an extraordinary occasion. “Ultimately, it’s down to the individual. Some people are born to perform. Some people need to work hard to control themselves. I like to keep my normal life under wraps but in front of 80,000 people, I’m going to perform. I’m going to beat Carl Froch.”