Caroline Weir will always remember that jolting month.
One week she was preparing for her high school prom and planning a teenage holiday, and then suddenly she was a professional footballer just like Kelly Smith, Rachel Yankey and Alex Scott: "all these Arsenal legends I'd looked up to growing up."
Weir is the attacking midfielder bewitching the Women's Super League as her idols did before but if she has matured on the pitch at Manchester City, she was moulded off it at Arsenal.
Her story until then had been a familiar one to so many in the women's game: the lone girl in the local boys' team, her obsession an oddity to some onlookers but not to the supportive parents who watched their daughter practise diligently past daylight so often that they were compelled to install garden floodlights and a patch of astroturf.
Hibernian offered refuge, the drive to training from Dunfermline a two-hour round trip on a schoolnight, but making it seemed unlikely to the 18-year-old until an unexpected offer from fellow Scot and then-Gunners boss, Shelley Kerr.
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"It all happened so quickly - it was a massive transition for me," Weir says as she prepares for Sunday's reunion in front of the Sky Sports cameras.
"I'd come from a small town in Scotland, from a loud family house with my brothers and sisters and I was living in a flat by myself where I didn't know anyone.
"It was a challenging environment to come into as a young player. Some things didn't go my way; I was on the bench, I found training difficult, being away from home was really hard.
"But I wouldn't change any of it. They were important years for me as a person, as well as in my career. It encouraged me to grow up quickly and become resilient. It made me tougher."
A fixture against the club where she spent her formative years will stir old feelings of the flat near Boreham Wood and the mental fortitude that was needed to navigate a new chapter but there is no time for sentiment.
City's Champions League qualifying exit to competition debutants Real Madrid, followed by a cruel league defeat to Tottenham - where a late goal ended a 33-game unbeaten home run but should never have stood - has been debilitating.
It has felt an oddly false start for Gareth Taylor's side, hampered by a pre-season truncated by the Olympics and shorn of injured key players like Lucy Bronze, Chloe Kelly and Keira Walsh.
Weir, one of 10 City players to have represented Team GB in Tokyo where a penalty shoot-out defeat at the quarter-final stage ended their tournament, missed the home defeat to Spurs, as well as Scotland's World Cup qualifiers, with a knee problem of her own but the break, she believes, has been healing to mind as well as matter.
"It was disappointing not to go away with Scotland but I think it was the right decision because it gave me a bit more time to rehab my knee, get in the gym. I hadn't had time to do that properly after coming back from the Olympics because it was straight into the games but I'm feeling good now.
"Real Madrid, Tottenham, they were challenging moments but we have to reset - and reset quickly. Everyone's looking fresh and sharp. Usually, international windows come at a bad time when you've got momentum but I think the window came at a good time for us."
Weir, fresh from another gym session, is out to build on her most productive WSL season to date.
There were spells with Bristol City and Liverpool after two years with Arsenal but in Manchester, she has established herself as one of the league's most progressive players, now unleashed to wield an even greater threat.
Under former boss Nick Cushing she had helped anchor midfield alongside Walsh but there was always a drive to operate in the danger zone, a propensity to dribble with her easy balance and close control, a penchant to shoot from range with her crisp technique.
Casual observers of the women's game will recall the opening-day rocket that settled the WSL's inaugural Manchester derby; a touch to trap a loose ball and then a searing strike that last year earned a Puskas Award nomination. Better still was the drag-back and deft lob - again against United - back in February.
Taylor deployed her in a more advanced role last season and it paid off.
She feels at home drifting between lines and pulling into pockets and she is finishing chances as well as creating them; a yield of just three goals in 2019/20 rose to eight last term, all of them from open play.
"I remember being told when I was growing up to be more greedy and shoot more!" she laughs. "It's always been encouraged.
"I think it's actually a trend in the women's game, being selfless, not taking enough shots. The way we play here, it's about shooting at those specific moments - you certainly hear about it if you're in a moment where you should play someone in but you don't! - and I think my decision-making has developed in that sense over the course of last season.
"But I'm naturally a more forward-thinking player as a midfielder. The final third is where I like to be, whether it's creating chances or scoring. The manager saw that straight away when he came in.
"Nick did too but we played slightly differently - I found myself a bit deeper at times. The way we play now there's a clear role for me as a No. 10, playing on the left-hand side, and it's all about the final-third actions; sliding in Lauren Hemp or Ellen White, getting on the end of crosses. The manager wanted me to get my stats up. It was a positive season, consistent - especially the second half - so it's about building on that."
City collectively are desperate to build on a frustrating series of second-place finishes but despite the early setbacks, there is inspiration all around the shiny facilities that Weir says leaves the women's team feeling firmly part of "the City brand".
Pep Guardiola will sometimes wander over to watch training sessions. Taylor's analysts will scour the Spaniard's playbook for educational passages of play. Weir can even pick the brains of Kevin De Bruyne: "My favourite - everybody's favourite!
"He's a top player but a nice guy, too. Hearing him speak tactically about how Pep works is really interesting. I love watching the men's game because we work on similar patterns of play.
"A lot is about positioning - seeing how the No. 8, 10 and 6 are trying to play together, and looking at how they build play from the back, too. These guys are operating at a top, top level but I love seeing what they're trying to do. We'll watch some clips when we're doing our own analysis sessions - it's all integrated here."
Off the pitch, staff have teamed up with scientists at the English Institute of Sport to further understanding of female athlete health, focused on menstrual cycles. It feels significant not just to normalise a subject that has traditionally been absurdly taboo but also to seek insight that goes deeper than tangible metrics.
"You feel that they're pushing the boundaries all the time," Weir says.
"When I first joined it was clear they were leading the way but they're always proactive in terms of thinking about what can affect your performance. Your menstrual cycle plays a massive factor in performance; we'll speak about in our team but outside of female athletes, it doesn't usually get talked about.
"We have access to some of the best, whether it's sports science, nutrition, strength and conditioning; you feel supported, it's a great place to be."
Weir's contract runs until 2022 and while she insists her focus is on "getting the best out of myself to help the team go and get some trophies," she is clear in her content. "I'm really happy. I feel supported, I'm happy in Manchester. There are things I want to achieve here."
There is a buzz right now, Guardiola's side embarking on their latest title defence against a United squad given Cristiano Ronaldo stardust, Taylor's crop out to hold off a freshly ambitious city rival as they plot their own trophy targets.
"Football's such a big part of the culture here. United are now pushing it in the women's game, trying to be successful. It's good for us - the derby's a massive game - but it's getting Manchester talking about women's football. It's great for the game as a whole."
Weir, who has won a League Cup, two FA Cups and almost 80 caps for her country, could barely have imagined the game's evolution as she did those keepy-ups in the back garden. Nor the heightened recognition: back in proud Dunfermline, her face looks out from the side of an Indian restaurant on a mural, a bolt of Scotland blue lifting slate grey.
"It was a dream for it to be the way it is now: walking out into major stadiums, playing Champions League and World Cups, having the facilities we have at City.
"We can't forget how far the game's come but equally we need to keep pushing forward. It would be great to see even bigger crowds; it's all about momentum - hopefully after the last 18 months with the pandemic, things are going back in the right direction."
Now City must get back on track.
They lost only once last season - to champions Chelsea - and still were left looking up for a fourth successive season. Taylor has admitted his side, in a 12-team league where small margins are trimmed further, must be "pretty flawless until the end of the season."
Arsenal have already beaten Emma Hayes' heavyweights, 21 goals in just six games across European and domestic competitions an ominous sign of their own intentions, but Weir believes her team-mates can thrive in adversity.
"I think we're probably better when we're up against it a bit; when we have that bit of pressure on us and we can't afford to drop points.
"We dropped points early last season and it spurred us on and made us more consistent. We seem to make it hard for ourselves but I'm confident it will bring the best out of us.
"It's a huge game for both clubs in terms of the league table. I think it's going to be a great one for people watching on TV, too. We know it's going to be tough but we're ready."