An eleventh major trophy with Chelsea for Emma Hayes on Sunday will not protect her from the pang of sadness at it being somebody else’s last.

No matter her insistence — and who could argue with her on this point? — that “there shouldn’t be any shame when there’s an ending to something”, or that “to be happy in life […] doesn’t always mean that our interactions are forever”. Maybe a part of her will break out of her tactical trance to watch Ji So-yun just a little more closely. Just for a minute, squinting enough to see the stardust falling from the feet capable of a few more tricks than the rest. One more time, Hayes might think, like searching for the secret compartment or hidden door at a magic show, the telltale slit in the fabric or bulge in the sleeve. How does she do it? Do it one more time. Do it one more time. 

Hayes’ characteristic human touch, and the sheer force of personality among her title-winning squad, has always belied the insistence of the rest of the world that in football there is no room for sentiment — and Ji So-yun’s final interview with the club’s in-house media team is further proof. There were flushed, blotchy cheeks, and eyelids rimmed with tears; messages choked out to fans and coaching staff who would gladly watch Ji for years on a pitch where the sun never sets.

This is the human cost that comes with the departure of the WSL’s most critical foreign signing: a player with a lightness of step that not only disarms opponents but seems to imbue them with a peculiar brand of light-headedness. She manages to read the game both deeply and at speed, and at some point supercomputers will catch up. Processing speed: 2.0 GHz, 4.0 GHz, Ji so-Yun GHz.

Only last week did she win her fifth WSL title, almost single-handedly, after a first half when Chelsea, trailing to Manchester United, felt caught in a landslip, pushing against the current, the ground uncertain. The introduction of Ji was to see a player terraforming the landscape at will, winding and flitting her way through midfield with the certainty of Theseus following string through the labyrinth. Her slight frame masks the strength that allows her to leave a player horizontal with her shoulder or her feet. All the while, that enchanted string unspools besides her as time seems to slow down and speed up all at once.

You wonder which attribute struck Hayes first in 2013 on the afternoon she saw Ji playing for INAC Kobe Leonessa in the final of the 2013 International Women’s Club Championship in Tokyo. Ji — then 22 — had already been heralded as the future of football in South Korea, and scored the Japanese side’s third goal as they overcame Hayes’ Chelsea 4-2.

“Five, 10 minutes into the game, I think we were already trying to negotiate for Ji,” recalls Hayes, only half-joking. She is at Cobham, Chelsea’s training ground, and given less than an hour has passed since Chelsea announced Ji’s forthcoming exit the conversation has an undercurrent of sadness. “I turned around to my assistant and I said: ‘I’ve never seen a player like her. I really haven’t’. And I still feel that way. I’ve never seen a player like Ji in the women’s game.”

Neither had the WSL, in more ways than one. Almost 10 years on, it has had only three other players from South Korea: West Ham and Spurs’ Cho So-hyun, Manchester City and Brighton’s Lee Geum-min and Bristol City and Reading’s Jeon Ga-eul, who has since moved back to Asia. The process of bringing Ji was complex — Hayes describes it as involving “lots of translators and lots of meetings in Japan” — but also one Chelsea had planned from the outset.

“We were aware of Ji from her exploits in the [2010] Under 20s World Cup, where she won the silver ball,” remembers Paul Green, Chelsea Women general manager and formerly Hayes’ assistant manager. “We were aware of her as a player, but the first time we saw her in the flesh was in that tournament. One of the main reasons we went to that competition was to try and secure the signing of Ji, to conclude a deal before we left.”

Two of those who helped things along didn’t even realise they were doing so. With a helpful stroke of timing, two players who had worked under Hayes during her time in the USA’s ill-fated Women’s Professional Soccer (WPS) league were now playing in Japan. “And I got them to speak to Ji for me,” says Hayes. “So I was probably lucky that I had a couple of players that were playing with Ji and thankfully gave me a reference. They were always raving about her, so by the time we got out there, it confirmed what we already known. It was a no-brainer.”

Becca Moros had played for Western New York Flash when Hayes was the WPS club’s technical director. When the division folded in 2012, Moros headed over to Japan with INAC Kobe, where a 20-year-old Ji was already making waves.

“(If she was) in America, she would just be coming out of college and be very underdeveloped and raw,” Moros says. “But she was just controlling everything about the game. She played off of people beautifully, and her ability to process information was so fast. She was reading so many different things instantaneously and had all the skills to be able to take advantage of those sophisticated things she could do in her head. There was an element of effortlessness; nothing was difficult.”

England lagged behind the world champions in its commitment to women’s football, but Hayes was at one of the clubs able to remedy the situation. “Emma was just starting to work things and build what she really wanted to build,” explains Moros. “The resources were not what they are now. We were so soccer crazy and on that team in Japan, the lure of the Premier League and the Champions League were mesmerising for female players who were just starting to see an opportunity to have that same kind of experience in women’s football. Emma was really our first window into hearing about it in a real, deep and concrete kind of way. Ji was really interested in and obviously loved Chelsea — it was like a childhood dream — so I shared information back and forth freely.”

Moros was not not formally involved in negotiations — “we never talked about numbers or contracts” — but as one of the few English-speaking players on the team at the time, she was able to build relationships despite having “no idea whether that was going to turn into something or if something serious was going to transpire”.

“I guess a bridge was formed maybe through my conversation and dialogue back-and-forth,” she says. “Everybody was interested in Ji. It started out as complimentary — people talking about her her talents and qualities, and being able to share them with (Ji). It started out very friendly, the sharing of cultures and talking about the qualities of different leagues.

“At this time in women’s football, this is how all conversations happened. You got places because you knew people, and you could have those conversations when other people couldn’t figure out how to get a conversation. There just weren’t the agents. It was very much dependent on your network. The world is so different (now), and no deals happen the way those deals were happening.”

Beverly Goebel Yanez, now the assistant coach at NJ/NY Gotham FC in the NWSL, also played for Western New York Flash during Hayes’ time at the club, before moving to INAC Kobe. After that 2013 meeting with Chelsea, Hayes was effusive in her praise of Ji when chatting with her former colleague. “It was just so casual,” says Goebel Yanez. “‘She’s so good!’. I’m like: ‘Yeah — I know! I see it every day in training’. I couldn’t help but brag about her. You come across those players in your lifetime where you just can’t help but say: ‘They’re just unbelievable’. You just can’t quite explain what it is, but they’re just special. When you have a player that is so incredibly gifted with their ability to understand that the game is grey and execute within that grey — I have nothing bad to say whatsoever. She takes that time at training to understand those players around her and what their needs are.

“It wasn’t conversations of: ‘How do I get her here?’. There was no intent behind it — it was so organic and so natural. I never saw it at the time as some sort of liaison.” She had conversations with Ji about her future plans — again, informally — but the language barrier was such that often they relied on body language and Goebel Yanez jokes that she would call home and say that she was “playing Pictionary 24/7”. Thinking that she might have played a hand in sending one of the world’s best players to the WSL is “wild”, but she does not want to give herself any credit. “Ji set herself up with who she was and what she brought to the game for any opportunity that that kind of presented itself,” she says.

Green recalls how, on the eve of the final, they met Ji in “a baseball bar in Tokyo” along with her agent, “who didn’t speak very much English, and we didn’t speak any Korean. It was quite difficult to understand everything that he was trying to get across in his broken English. However, it was very clear, from what we could make out, that there was a very serious possibility that she wanted to come to Chelsea, and he was tasked with making that happen.”

In a previous window, Chelsea had made Yuki Ogimi the first Japanese player to feature in the WSL. A World Cup winner, she had played in the Olympics the year previous and had a Champions League winners’ medal from her time with Turbine Potsdam. “She was a real statement signing, and I think that really opened up the thought of other players to come to Chelsea and the WSL,” Green says. “Before we flew home, Ji’s agent came to the hotel to meet me at half five, six in the morning for a second meeting about how we can make it happen. When we returned to the UK, we formally made an offer.”

At Kingsmeadow, a member of the Chelsea Women Supporters’ Group hands Ji a card plastered in selfies and photographs and with scores of messages inside. “From my first game in 2014 you were unreal and have never let us down once in all that time,” reads one. “You were there at our very first game and will be missed so much,” adds another.

Ji has embodied the Hayes era — not so much part of the furniture as part of the air everyone was breathing — with the kind of persistence that has brought her five WSL titles, three FA Cups and two league cups. The only drawback to being so synonymous with the club is that everyone might overlook just how well Chelsea did to sign her in the first place, given how sparse video footage was at that time.

“Certainly back then, it was very difficult to get footage of this league, never mind the Japanese league where she was playing,” Green says. “The international footage was really what you could access. Scouting back then was a case of getting on a plane and going to watch players live if you wanted to get a closer look. Now, you can access games online. The recruitment was pretty much Emma and I. Now, we have dedicated people in scouting positions who do the majority of watching of games. They put in reports and recommend players for us to take a look at, rather than [us] doing everything from start to finish like back then.”

Moreover, the WSL was five years from turning fully professional. “If somebody would have said to us in that meeting back in Tokyo that we would have had Ji for eight years, I don’t think anyone would have quite believed that because of where our game was in this country,” continues Green. “All the clubs were pretty much part time. To have a world star — you just wouldn’t believe that we’d be able to keep somebody [like that] for as long as we have. But I think that’s down to the growth of our club and game over here. It’s been a good relationship. We’ve been good for her, she’s been good for us and we’ve grown together over that period of time.”

“I think the difference in the game is where there’s less free agency [and] the playing pool is much smaller, the risks are much higher because the teams are at another level,” Hayes adds. “It gets even harder to make a decision. You might have taken more risks early on. Now, it’s like is: is that player really going to take us to the next level? It takes a lot longer to actually get to the player now. What used to be, even then, a six to twelve month period is much longer now.”

Ji was met at the airport, after signing, by Green and one of her friends living in London and willing to act as a translator; she lived with team-mates initially and then moved in with a Korean family. There is a large Korean community in New Malden, a suburb of south-west London not far from Chelsea’s home ground, but regrettably, the community has not followed Ji’s Chelsea exploits as enthusiastically as it could have.

But there is a knot of South Asian fans — originally from China, now gathered from Elephant and Castle, Vauxhall, Aldgate, and Southampton — making their first trip to a Chelsea game solely because “Ji is leaving”. Two South Koreans have joined them.

“She is a great women’s player,” says one. “It’s a sad time. We came to see the occasion.”

Do they wish they had come earlier? “Yes,” they say, unanimously. “Because for our Asian community, there’s not a lot of athletes competing, especially for women,” adds another. “I think most people just focus on men’s football. The followers of Ji So-yun can’t compare with Son Heung-min. It’s sad that they didn’t put a lot of attention on women’s football. The China Women’s team won the Asian Championship during February and most of people are starting to focus on that because the male team have had a terrible season.”

Ji’s national team manager, Colin Bell, believes that she “could play at the highest level for the next three to four years”, by which point Ji would be 35. Bell has changed the playing style: Ji has moved from a No 10 to a “free role”, he says, and, since then, deeper so that she can “get on the ball much quicker, much earlier, and bring the other players into play”.

Any manager would want Ji on the ball as much as possible, but Bell has also benefited from her brain. “In German, we have a phrase: verlangerte arm,” Bell says. “It’s a little bit difficult to actually translate, but it’s like an extension of your right hand, an extension of one’s self. It’s a very big compliment. We can discuss tactics, talk about things, because her understanding and game intelligence is high if we need to adjust things very quickly. She reads the game very well and very quickly.”

“It’s important to remember that Ji is without doubt the best international player (brought) into the WSL, ever,” Hayes says. “She is a dream to watch. And Ji at her best — I don’t think there’s been anyone better in this country in the last 10 years. She’s mesmerising.” Her voice is laced with emotion, and her eyes, glassy, almost give her away. “She’s left — phwoar — a massive stamp stamp on my heart. She’s an Emma Hayes footballer.

“I’m so, so grateful for everything she’s done for me personally, because I think she stayed with the club at times when she could have maybe gone abroad and done other things. She placed her trust in me and in the club. And that loyalty is what sets her apart. I’m going to miss her terribly as a human being but I’m invested in Ji’s life. I know that it was an agonising decision, but, to be honest — and I know Chelsea fans won’t like this — I think it’s the right decision for her, even if we lose an iconic figure.”

But still — still! — part of Hayes might wish that she could stop time. Watch Ji for a little bit longer, lingering over the turns, the trickling runs; watch Ji, suspended in one swooping dart goalward, without thinking about the ending. But only one Chelsea figure can freeze time, and after the FA Cup final on Sunday Ji will spirit herself away.

Lead graphic: Sam Richardson, Getty Images