He arrived in Germany as an untried 17-year-old and leaves the Bundesliga as one of the most exciting players on the planet. This is how Jadon Sancho's time at Borussia Dortmund made him into the world-class England international he is today.
Sancho landed on German shores in August 2017, with Dortmund securing the signature of the teenager from English Premier League outfit Manchester City as he looked to the Bundesliga for greater first-team opportunities.
The club were initially cautious of unleashing their newly acquired prodigy, as Sancho was given time to acclimatise in the youth and reserve teams. But that would soon be addressed at the midway point of the 2017/18 campaign, with Sancho handed his professional debut against Eintracht Frankfurt on Matchday 9.
"I was so nervous," the Londoner later told FourFourTwo magazine. "Scared even. [Ousmane] Dembele had just left and the fans were thinking 'Who's this No.7? He must be a big thing.'
"I'll never forget my first dribble. I tried to take on their full-back, he tackled me and I dropped to the floor. I couldn't get back up. Welcome to adult football, eh? I thought I had so much time and could do my own thing, then BANG! I knew I had to release the ball quicker after that."
On reflection, those first formative steps into senior football jar with the daring, edge-of-your-seat winger that now graces the field and Sancho would soon put to bed any doubt over his ability to adapt to "adult football".
Specifically, you can mark 21 April 2018 as the date Sancho truly showed the world that he was ready, and worthy of all the hype. And he did so emphatically, with a dazzling display against Bayer Leverkusen in front of the world-renowned Signal Iduna Park faithful.
Watch: Sancho's Bundesliga breakout against Bayer Leverkusen
It's safe to say that Dortmund's famed Yellow Wall has seen some incredible things in its time and anyone that was there that day will have Sancho's star turn embedded firmly in their memory.
In only his fourth start, and ninth BVB appearance overall, Sancho tormented Die Werkself, scoring the opener after just 13 minutes before then teeing up Maximilian Philipp and Marco Reus to complete a 4-0 rout.
"The way he controlled the ball to set up the third goal - that shows everything," Dortmund skipper Reus said after the win. "I wasn't that advanced at his age. So much respect!"
Reus wasn't the only man throwing Sancho his props as a result of that performance, and the winger hasn't slowed down ever since.
By the start of the 2018/19 season, Sancho was already one of the first names on the Dortmund teamsheet and he ended the campaign as the Bundesliga's top assister with 14 league provisions as the likes of premier providers Joshua Kimmich, Filip Kostic and Thomas Müller and the rest of the division were left trailing in the youngster's wake.
Watch: Sancho dedicates Revierderby winner to his grandmother
That first full season also saw Sancho add 12 league goals of his own to the Dortmund cause, while he found the back of the net in the UEFA Champions League for the first time and also hit a Revierderby winner against Schalke just days after the death of his grandmother.
"The goal means everything to my family," Sancho said at the time. "Sadly, my grandmother passed away, so that goal was for her. I'm glad that I got the goal and helped the team to get three points."
He continued to honour her with superb display after superb display in 2019/20, where Sancho began the campaign by scoring one and setting up the other in Dortmund's 2-0 Supercup win over Bundesliga champions Bayern Munich.
That was the first club trophy of his career and by the end of the season, Sancho had contributed 16 assists and 17 goals in the league. It took a Bundesliga single-season record for Müller (21) to beat Sancho to the assist king crown, while only out-and-out strikers Robert Lewandowski (34) and Timo Werner (28) boasted better returns in front of goal.
Watch: Sancho's Bundesliga highlights
Sancho was again in the league's top-five for assists in 2020/21, as the now 21-year-old's continued consistency confirmed that he was the real deal.
Those claims were bolstered with remarkable efforts in cup competitions, as Sancho scored six goals and laid on five assists in six DFB Cup appearances, including two goals and an assist in the 4-0 win over RB Leipzig in the final. The 2020/21 competition's top scorer was on target in every round of the German Cup bar the semi-finals, where he was content with providing just the two assists.
In Europe, meanwhile, Sancho scored twice and set up three for his teammates in six UEFA Champions League outings. Arguably, Dortmund could have gone even further in the tournament had Sancho not missed both legs of the quarter-final meeting with old club City through injury, and it's little wonder that he is now being described as operating at the top of the game.
"He's absolutely world-class," said former Bayern and Germany midfielder Dietmar Hamann. "In one-against-ones, there's nobody better than him right now. He's two-footed and can play on either side, shifts his weight fantastically and is technically perfect."
Former Dortmund coach Lucien Favre drew the same conclusion as early as December 2019, telling SportBild: "Jadon's a world-class player, no question about that."
There certainly isn't any doubt about that and, all in all, the Englishman has played a part in 108 goals (50 goals, 58 assists) in 137 appearances for Dortmund in all competitions, meaning there is a Sancho-crafted BVB goal every 92 minutes they play.
His Bundesliga record alone is just as jaw-dropping: 104 appearances, 38 goals, 45 assists. That combined goal involvement of 83 boils down to Sancho influencing a Dortmund league strike every 90 minutes. And Sancho's emergence has not been limited solely to club football.
Already crowned player of the tournament as England lost out in the 2017 U17 UEFA European Championships final, Sancho went one better and became a FIFA U17 World Cup winner just two months into his Dortmund stint. He scored three times and set up two more in just three group stage appearances in that tournament, before heading back to his club prior to the knockouts.
Youth international football would soon come to an end for Sancho, who made his full England debut exactly one year on from featuring at the U17 World Cup. The then 18-year-old was handed the first of his 20 caps to date as a late substitute against Croatia in the UEFA Nations League and he has since scored three goals for the Three Lions. In that time, Sancho has established himself as one of his country's most potent attacking options.
He now leaves Dortmund having earned a number of club records, becoming the first player born in the 2000s to score twice in a single Bundesliga match, and youngest Dortmund player to hit a Bundesliga double. He was also the first player born in the 2000s to score a UCL goal for BVB, was the youngest man ever to bag eight and then nine goals in a single Bundesliga season, as well as Dortmund's youngest player to reach double figures in the top flight.
Having come to the Bundesliga in search of greater opportunity, it's safe to say Sancho was not only given plenty, but that he took the majority of them in devastating fashion. The result is a world-beating winger, made in the Bundesliga.