The smile. It’s always the smile. Start a conversation about Heung-Min Son and a reference to his sunny countenance will crop up at some point. It’s as inevitable as… well, the sun coming up in the morning. And with good reason – just take it from the man himself. ​

“When I was a child, I loved this ball,” he says. “I loved playing with this ball. Why should I not smile? Of course, I don’t want to lose, but I enjoy playing football. I love to see the stadium. I love to see the opponent. I love to see everything. I enjoy every single second, every single game, every single person coming to the stadium and watching on TV. This is my dream. Why should I not smile?” ​

This is a smile that has even adorned ice-cream cones back in his native South Korea. Son repeats himself as if to underline the point: “Why should I not smile? Why should I argue about something? It’s nothing, it’s nothing. I just want to smile with this ball and enjoy this moment.”

As 2019 gives way to 2020, the newly crowned AFC Asian International Player of the Year can look back on 12 months containing many moments to enjoy. On his return to north London from the year-opening Asian Cup he struck for Spurs in four consecutive games – including their opener against Dortmund in the Champions League round of 16 – leading the line impressively while Harry Kane was injured. In April he hit the first Premier League goal at Tottenham’s new stadium, followed by three of their four across two legs of a Champions League quarter-final win against Manchester City. ​

“I’LL NEVER BE HAPPY WITH MY PERFORMANCE. I TRY TO BE BETTER EVERY SINGLE GAME. ESPECIALLY IN THE CHAMPIONS LEAGUE.”

With another five in this season’s group stage by the end of November, that made it nine in 11 Champions League games – one goal more than Lionel Messi in the same period. Small wonder then that the 27-year-old was the highest-ranking Tottenham player in the recent Ballon d’Or vote.

It’s not been all smiles though. At the final whistle of the Champions League final on 1 June, no Spurs player looked more disconsolate. This season there have been more on-field tears, after his challenge on André Gomes in a Premier League fixture left the Everton midfielder with a fracture dislocation of his right ankle. A fresh sadness came with the November departure of Mauricio Pochettino, the manager who “brought the club to the next level”, as Son puts it – and who, moreover, was responsible for enticing him to England from Bayer Leverkusen in 2015.

“Still there is sadness when I speak about him because he brought me here, he made my dream come true,” says Son. “He gave us many, many opportunities to play here [in the] Premier League, Champions League.” It was discussions with Pochettino that eased Son’s anxiety over a difficult first campaign in England, when he only managed to make four 90-minute appearances.

Since then he has flourished. His selfless approach has ensured that he has thrived in several positions across the Spurs attack, most commonly on the left side. Not surprisingly his new manager, José Mourinho, has already declared himself a fan – he even likened him to the great Brazilian Ronaldo after a wonder goal against Burnley in the Premier League, on the same December day that he collected his AFC Player of the Year accolade.

“Before this goal my son calls him Son-aldo and today he was Son-aldo!” said Mourinho after Son had picked up the ball deep in Spurs territory and torn through half the Burnley team to score a goal that was a triumph of speed, directness, balance, composure and calm finishing. “I think it’s a bit lucky as well,” the man himself grinned afterwards. “The pitch was long!” ​

In person, Son, sitting in a navy-and-purple tracksuit in the auditorium at Tottenham’s training ground, is everything you’d expect: cheerful, courteous and obliging. Indeed, that famous smile is never far away. Yet beneath the good manners, there must be an edge, right? To get where he has in professional football demands it. His humility is such that he happily suggests he’d finish last among his team-mates in a general-knowledge quiz – “I just want to be fair, I think it’s me.” Yet put him out on a pitch, even a training pitch, and that professional pride kicks in; only Dele Alli, he reckons, can outdo him for nutmegging team-mates. “When we play boxes, I try all the time [to nutmeg people] – there are always arguments. When I try, they say, ‘Oh, please stop this.’” ​

It’s more than an edge: it is a deep drive that has taken him from Hamburg, where he arrived as a 16-year-old and spent his first three seasons as a professional, to a prominent role as one of the Champions League’s most productive forwards. It is a drive that means he wants more from himself, always. ​

“I’ll never be happy with my performance,” he admits. “I try to always improve – I try to be better every single game, especially in the Champions League. I want to do better. This is a competition in which I have always dreamed to play. I think I could do better. I know I can do better.” ​

It’s not hard to locate the source of this drive: Son’s father, Woong-Jung Son, is a former professional footballer. “He’s my father and so important for me in life and football. When I was young, he was my football teacher – an experienced footballer. And yes, he’s given me so many options. I think it’s very important to have this father, for me. We still talk a lot about football, have fun and watch it together.”

"IT'S JUST BEEN CRAZY AND THAT'S WHY I WANT TO BE BETTER, I WANT TO IMPROVE. WHEN THEY SEE THE CHAMPIONS LEAGUE GAMES, I JUST WANT THEM TO ENJOY WATCHING. THAT IS MY ANSWER TO THEM."  

When Frank Lampard was a boy he would be taken out by his footballer father, Frank Lampard Sr, to perform running drills. These exertions built up the speed and stamina that served him so well throughout his career, allowing him to break into penalty boxes from deep to score the many goals he claimed in Chelsea blue. Son, growing up in Chuncheon, northeast of Seoul, had his own “basic training” routine, as he calls it, imposed by his father. ​

“It was almost seven or eight years that I was working with him and every day it was the same programme,” says Son. “So, yes, when I was a kid it was a bit tough to do the same programme every single day but I think I realised, when I grew up and became a professional, how important that was. I am so grateful to have had that basic training. Sometimes people forget how important the basics are – but for me it was really, really important to have that programme and project with my father.” ​

Said programme included a lot of keepy-uppies. “Keep-ups was almost one-and-a-half hours,” explains Son. “If I dropped the ball I had to start from the beginning, so it didn’t matter how long I had been [doing it]. This kind of thing we had worked out: keep-ups, dribbling, passing. We progressed but I think the start of every training session was always keep-ups. It was really tough but I think I enjoyed it a lot.”

Today Son’s mother, Eun-Ja Kil, and father live with him in north London – and those lessons keep coming. “I can’t train with [my father] but we talk after the game, because he comes to all the home games,” he says. “We talk about situations and how I can do better, because his view is actually better than mine. We try to have a conversation about situations and we still really enjoy these sorts of things.” ​

The focus on football is such that his father has even spoken publicly about his preference for Son to remain single until his playing days are over. As it is, life in London for Asia’s most expensive footballer is rather low-key, it seems. “I go shopping, I go for dinner with my parents, and when my friends come round we go out in the city,” he says. “I’ve been to a Korean restaurant here in London a few times. Obviously it’s not the same but I can feel like, ‘Yes, this is my home food’ when I miss [it]. Of course, my mum cooks and everyone says that their mum’s food is the best food ever. But sometimes I don’t want to let her cook too much for me, so we go together to ‘Koreatown’ or Korean restaurants and I have a nice time with them.”

The ‘Koreatown’ he’s referring to is the Surrey commuter town of New Malden, home to the UK’s largest Korean community. As it happens, Tottenham Hotspur Stadium has its own growing Korean presence too – a sprinkling of South Korean flags can be seen at every home fixture – and groups of fans from the motherland are a regular sight outside Spurs’ training ground. ​

That said, these are still mere ripples when set next to the sheer adulation for Son back home. “I enjoy it when I go to my hometown, when I go to South Korea, and I try to be nice to those people if they recognise me and it’s not that crazy.” ​

There is a pub for Spurs followers in Seoul called O.Goal.Gye (‘To dare is to drink’ is its tongue-in-cheek motto), where not even the timing of Champions League kick-offs acts as a deterrent. “It would be in the morning – at 4am, 3am – but the people still watch and they still support me,” he says. Does that bring a sense of responsibility to pay them back in some way? “It’s really great that, because social media is so big, I can watch all the supporters and how they support. It’s just been crazy and that’s why I want to be better, I want to improve. When they see the Champions League games, I just want them to enjoy watching. That is my answer to them.” ​

It is a far cry from the 1980s, when South Koreans would watch VHS recordings of their country’s first successful export to Europe: Bundesliga-based Bum-Kun Cha. He won the UEFA Cup twice: first with Eintracht Frankfurt in 1980 and then with Leverkusen eight years later. In one sense Son has emulated him already, with his two seasons in Leverkusen from 2013–15, but European silverware has thus far eluded him. Yet nobody did more to take Spurs so close to the continental crown last term – and it’s clear that the disappointment still lingers. ​

“The journey was actually very positive – until the final,” he says. “Of course, after this, when you lose at the final stage, you are more disappointed. We worked so, so hard to be there and then after that game, we came away empty-handed. We were disappointed – really, really disappointed. As humans, as players and as a team. I can’t change anything; that was the result. We have to take it. But I think the journey made us even stronger.” ​

And, as ever with Son, he’s driven to do better. “If I’m there in the final next time, I just want to make sure. I just want to win and bring home the trophy.”