Jadon Sancho signed for Borussia Dortmund three months after they last won the DFB-Pokal in May 2017.

Back then, it was Ousmane Dembele and Pierre-Emerick Aubameyang who scored to see off Eintracht Frankfurt 2-1 in Berlin. Major transfers followed for both: Dembele was quickly on his way to Barcelona, a €105million replacement for Neymar, while Aubameyang left for Arsenal for a reported €60m the following January.

This year, Dortmund returned to the Olympiastadion for their first Pokal final since, with envious eyes from across the continent casting longing looks again at their best attacking talent: Sancho and Erling Haaland. Inevitably, it was they who settled the contest with RB Leipzig, and before the half-time whistle had even blown.

At least, it feels inevitable with these two. Haaland, who scored the second in a 4-1 win after shunting the imposing frame of Bayern Munich-bound Dayot Upamecano to the ground, has hit 55 goals in 57 games in just under 18 months at the club. Sancho has been directly involved in 105 goals (50 scored, 55 assisted) in 135 Dortmund games. These are breathtaking returns for two players who weren't even teenagers when Dortmund last won the Bundesliga in 2012.

Haaland has always seemed an outlier in the expected development of a young footballer; a striker of such prodigious physical and technical gifts that it seems entirely plausible he was grown in a number nine laboratory. Dortmund are convinced they will keep him for another year and they probably will unless a European giant is capable of throwing a pandemic-defying nine-figure transfer bid their way.

Sancho's rise feels different. He is the product of calculated gambles as well as divine gifts. He is the 17-year-old boy who uprooted from Manchester City to speculate on game time in Germany, who made himself undroppable for one of the country's greatest clubs and was in the team of the season before his 20th birthday.

On Thursday, he was the best player on the pitch as Dortmund ruined Julian Nagelsmann's Leipzig farewell tour, as he became the youngest player to score twice in a DFB-Pokal final – at least until Haaland surpassed him. The transformation from brave kid to matchwinning bravura was complete. This was the dawning of a superstar.

His first goal, a curling effort from the kind of area Thierry Henry spent a career exploiting, was a thumping reminder of his finishing skills. His second was impudent footwork, as he collected Marco Reus' cut-back, danced inside the covering defender, and waited for Peter Gulacsi's despairing dive before putting the ball in the net.

Alongside Reus and Haaland, Sancho was a roving, controlled menace. He drifted into space to the side of the Leipzig back three but timed forward runs to perfection. His performance trod that fine line of spontaneity and foresight: unpredictable for defenders, while his team-mates knew where he'd be. Such a display can only come when talent meets application, and lessons are learned. For a 21-year-old to do it is remarkable. He even managed to make a total mess of overplaying a one-on-one chance before another counter-attack saw him set up Haaland for the fourth late on. He's still learning.

We may be in the final weeks of seeing Sancho as a Dortmund player. You can bet Manchester United's interest will only strengthen once Ole Gunnar Solskjaer watches back the highlights of this game, and they won't be alone. With a "gentleman's agreement" in place with Dortmund over his future, this could well be the transfer window where they elect to cash in.

They will do so in the knowledge that Sancho's journey to stardom is complete.