It was the happiest Luke Shaw had ever been to take a whack from one of his team-mates. “A proper swipe, too,” Shaw remembers, reaching down to the part of his right leg where Ashley Young had connected in training. A bad one? “Not enough to knock me over, but you could hear the crack against the shin-pad. It was the first time anyone had really kicked me since I started training again and as soon as it happened, Youngy’s reaction was [hands up to his face]: ‘Ah, shit.’

“Nobody had wanted to be the one to do it. You could tell he felt really bad - ‘Shit, are you OK?’ - but he didn’t have to. He’d hit my leg and it was fine. ‘I’m good, I’m good.’ And I was. I was really good. It was fine, and I’d needed that kick.”

It is coming up to a year now since that moment - 7.59pm, 15th September 2015 - under the floodlights of the Philips Stadion, PSV Eindhoven versus Manchester United, when Shaw’s leg was shattered like a broken cricket stump.

Type the words “10 most horrific football injuries ever” into Google and you can find the video. It comes with an advisory you should be 18 or over and it certainly isn’t for the squeamish bearing in mind Shaw’s own recollections conclude with him sitting on the pitch “holding on to my thigh and looking down at the rest of my leg, and it was just kind of hanging there”.

In another era, an injury of that nature might have wrecked a footballer’s career and, for Shaw, it has certainly been a long slog to reach this point where he is back in United’s team, playing with distinction once again and possibly about to resume his England career. The man sitting here today, much like his club as a whole, seems happy for the first time in a long time. “It’s hard to describe how good it feels,” are his first words when the tape goes on.

Yet there are glimpses of hurt, too. Shaw is speaking in-depth for the first time about the double break, his rehabilitation and how the past year has affected his life, and it quickly comes across that the suffering was mental as well as physical. It is only recently that he has stopped watching the various footage but, for a while, he often found himself looking back on what happened, trying to make sense of it.

“I partly blame myself,” he says. “I’d run into their penalty area and I should have shot with my right foot but I wanted to come inside. I wanted to be on my left foot. And then, obviously, the tackle. I don’t even want to think about the tackle, to be honest. At the time I thought: ‘Give him the benefit of the doubt, it wasn’t actually a bad tackle.’ But the more I’ve seen it since, the more I think: ‘You know, that was actually a really bad challenge.’”

The player in question is Hector Moreno and though Shaw has no appetite to pick a fight, his views have certainly hardened over time. “To be fair to him, he did come to say sorry. He came to the hospital and I saw him face to face in my room. I was quite sympathetic at the time - ‘Aah, look, you can come in, it’s fine’ - but at the end of the day it was me lying there with a broken leg, and I went through so many bad times since then I did start thinking about it some more.

It really annoys me they [Uefa] gave him man of the match. Some people were saying it was a good challenge, others were saying it was a bad challenge. For me, it’s a bad challenge.”

Briefly he did wonder if he would ever make it back. “I remember I said I didn’t know if I was going to play again. I didn’t properly think that, but it did go through my head a couple of times at the start,” Shaw says.

“Now, I don’t like looking at the video any more because I’ve probably watched it enough. But I can look at the pictures. Even now, I think: ‘Oh my God.’ I’ve shown a few of the lads. They don’t like them either and I can remember, on the night, Memphis [Depay] turning his head away because he didn’t want to look.

That night, lying in hospital, I swear to God the pain was something else. Oh God, the worst you could ever imagine.

“I was in shock, to be honest. The pain came later. I was just so upset because I knew I was going to be out for so long. You might have seen the picture where I had a tear coming down my face. They took me back to the dressing room and it was weird because at the start it didn’t hurt as much as I thought it would have. I remember getting my phone, texting my mum and tweeting everyone. It sounds mad, I know, but my leg was broken and I didn’t know what to do. I thought: ‘I’ve got to do something.’

“Then, that night, lying in hospital, I swear to God the pain was something else. Oh God, the worst you could ever imagine. My mum was next to me and I remember saying to her: ‘They have to do something because I actually can’t keep going with this amount of pain.’ They had to open up my leg to pull out all the clotted-up blood. They put me to sleep, but it didn’t stop the pain when I woke up again.”

Shaw tries not to be bitter because it is not his nature. One day, he says, he wants to go back to St Anna Ziekenhuis hospital in Geldrop to see everyone who treated him. “I want to say thank you properly. I want to give them a present because, look, [holds up leg] it is so good now. They were the best people, everything they did for me and my family.”

He also still has the banner - “Get well soon, Luke Shaw” - that the PSV fans held up when the team played the return game at Old Trafford and it would be a full-time job to reply to the tens of thousands of people who wrote to him.

Ross Barkley, who broke his leg in three places at the age of 16, was one of the many people offering support and advice. “But I’ve had so many messages I can’t just pick out one or two people,” insists Shaw.

“There were so many people - fans, professionals, ex-players - getting in touch. I had a lot of time obviously to go through Twitter and it was really nice to get so much support. The first couple of weeks it was non-stop. But I also remember someone saying: ‘As long as you know that’s going to die down in a few weeks and, after that, it’s just going to be you, focusing on getting back.’ And that did happen, too.”

That long period of rehabilitation was a gruelling, difficult experience. “I’d heard other players talking about dark times when they were trying to get back from bad injuries. I didn’t think I would be like that but, yeah, there were parts when I was thinking: ‘I just don’t want to be here any more.’ I could hardly walk for six months, never mind play football. I was limping for so long. I was walking with crutches - as in, properly walking - after about the first month because I thought it was much better to put my body weight on and build up the strength. But people have said I was still limping even after I came off the crutches.

“I still get aches. I don’t go a day without feeling it. It’s 100 per cent better but it’s normal, apparently, to feel it after such a bad injury. In the first three or four weeks when I started training outside it felt good, but then all of a sudden it started aching. It didn’t hurt, but it was aching and aching and even before I went out I could feel it and I was thinking: ‘Fuck ? is it ever going to go away?’”

In total there were four operations, leaving two three-inch scars either side of his calf. Shaw had his crutches for six months and he also saw a psychologist to help make sure he was in the right frame of mind to play again. “Most of it was about how it affected me,” he says.

“But I don’t feel I have come back any different. It’s harder for my family really. My mum was really nervous anyway watching me play but it’s even worse for her now. Whenever I go into a tackle she grabs hold of whoever is next to her because she can barely watch. But I’m fine. I’ve had a couple of times when someone has come across to tackle me and for a split second I’ve thought ‘Whoa’, but in the last game it didn’t even cross my mind.”

Now, Shaw says, it is about making up for lost time, particularly as it still nags at him that he did not “show what I could properly do” in his first season after signing from Southampton two years ago.

“I was only 18. I’d come in new and then all that stuff came out within pre-season,” he says, referring to Louis van Gaal’s public declaration that his new signing was not fit enough.

“It was my first couple of weeks and being so young it was difficult. I picked up an injury, I didn’t get a full pre-season, then I was out for four weeks.

“Loads of things. Maybe I took it a little bit easy over my time off after the World Cup. Maybe I didn’t think it was going to be as hard and as quick as it was. The stuff that happened, the injuries - it knocked my confidence a bit. Sometimes I didn’t feel right to play.”

That, however, feels like a long time ago now. Shaw has played in both of United’s wins so far under Jose Mourinho. A popular member of the dressing-room, he has quickly set about re-establishing himself as an attacking left-back of high ability and though he is not taking anything for granted, no one should be surprised if he is rewarded with a place in Sam Allardyce’s first England squad, named on Sunday. Even if not, a career of brilliant promise is back on track. “I’m loving it,” he says of living in Manchester.

“I live with my best friends from school, four of us. Some people might think we’re always partying but it isn’t a party house. These are my best friends - I’ve known one since we were eight - and they want the best out of me.”

They have their own chef - “it’s much better that way, much healthier as well” - and Shaw also has plans to do something that was impossible when he was operating on only one leg: take his driving test.

Mourinho, he says, has changed the entire atmosphere within the club and the admiration is mutual given this was the manager who tried, unsuccessfully, to gazump United’s initial £27m deal for Shaw and sign him for Chelsea instead. “We’ve had a little joke about it,” Shaw says. “He’s a cool manager. ‘Why didn’t you come?’ he wanted to know. I just felt I had more opportunity of first-team football here.

“But now I’m with him and I’m really happy he’s here. It hasn’t been the best few years but all of a sudden it feels really good, really positive. We feel we have that fear factor back where people are thinking this team is going to be hard to beat. I’m fit, I’m happy, I still feel I have a lot more to give. I just want to push on now.”

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