It irritated those here in Dortmund and even beyond when Jadon Sancho flopped at Manchester United. Born in London, perhaps, but they see him as a Bundesliga export.

When goals and assists that have flowed so easily in Germany suddenly dry up in the Premier League - see Timo Werner, also - it gives reason for the ‘Farmer’s League’ doubters to plough their contempt. The Bundesliga, for the record, have two teams in the last five of the Champions League, while England have none.

Sancho’s recovery, then, is about him, not the country in which he feels so at home. And that is why he is here, back at Borussia Dortmund, the club who turned him into that £73million export in the first place.

It would be easy to declare that the 24-year-old is reborn, given he is playing in the last four of the world’s premier club competition just four months after returning on loan. But that would not be accurate. Not yet, at least.

The Sancho who was shipped back from United arrived wearing a ‘damaged goods’ tag. He would not be the only young man to be broken by a move to Old Trafford, but the responsibility for performance rests first with the player, not the club. And that is the concern with Sancho, does he have the desire to make the absolute best of the talent that burned so brightly during his first spell at Dortmund?

Jadon Sancho is an improved player at Dortmund - but it would not be accurate to say he is a man reborn

Watch him now and he is not the same player. Never mind the numbers - three goals and two assists in 16 games - your eyes tell you that much. Here is a simple observation, but he seldom runs very fast anymore. 

There is something of Jack Grealish Version 2.0 about Sancho now, the safe model who looks shorn of expression. Gone are the dribbles, those daring darts down the wing or infield, the unpredictability that rendered the opposition helpless. Back then, the end product was predictable. His last season at Dortmund brought 36 goal contributions (16 goals, 20 assists) from 38 games.

When I spent some time with data analyst experts in the summer of 2020, they took me inside their system’s algorithm and what it told them - and the clubs they worked with - about the future performance of players. 

Fascinatingly, they boldly predicted that Werner, who had just made a £45m move to Chelsea from RB Leipzig, would not be a success in the Premier League. But I will never forget their confidence around Sancho. He was 20 years old at the time and he, they said, was a future Ballon d’Or winner.

He will never be that now, and you even wonder if his international career will forever be stuck on 23 caps, the last of which came nearly three years ago. Despite being one of only four Englishmen left in the Champions League, there is no talk in the UK or German media of a late push for the European Championship.

Rather, this is rehab, albeit amid the glare of the world. That is the pressure Sancho must prove he can shoulder. But he is evidently happier in these surrounds. He was the team’s best player and scored at the weekend, albeit in a 4-1 defeat at Leipzig. 

He also has strong allies in the form of head coach Edin Terzic and sporting director Sebastian Kehl, even if they admit the winger is not yet at the level of before.

At United, Sancho made enemies of those above him. He was an embarrassment to them come the end, made to train alone and banned from the first-team facilities. Here, his smiling face comes back at you from the window of the club shop in the shadow of Signal Iduna Park. That same face is on mugs, posters, T-shirts.

It will be on the pitch, too, when Dortmund take on Paris Saint-Germain this evening. That is where he can help make the case for the strength and vitality of his adopted home. More pertinently, though, it is his own health and wellbeing he must demonstrate.

Beyond this season, his future is unknown. Ironically, Dortmund’s development of the player first time around has probably priced them out of buying him back - United’s want to recover a large chunk of the transfer fee and Sancho’s wage expectation would be prohibitive for them.

Winning the Champions League would help, of course. And that was always his dream, when he played at Dortmund with Jude Bellingham and Erling Haaland three seasons ago. The three of them left to achieve their goals. Sancho, it seems, was better off here all along.