Above an inconspicuous mattress shop not far from the busy Pankstrasse U-Bahn station in Berlin, there are three cartoon faces graffitied onto the gray wall.
They are the faces of the Boateng brothers, Jerome, Kevin-Prince and George, while below them there reads a message in huge yellow letters: "Grown on concrete".
The artwork alludes to the Bayern Munich defender and his siblings' rise from the soccer cages of the Wedding district in Germany's capital to the academies of Bundesliga's top clubs and - in the case of Jerome and Kevin-Prince - beyond.
Torben Rhein is another member of the Bayern family who knows central Berlin's footballing 'fields' well.
The highly-rated teenage midfielder spent much of his youth playing on the rubber pitches with goals made from three metal rods at the inner-city Park am Gleisdreick.
There he would play against much older boys, learning how to make quick decisions and use both feet on the small pitches where the game 'winner stays on' regularly saw Rhein come out on top.
It should have come as no surprise. While Rhein was spending much of his spare time at the local park, he was also training with Hertha Berlin's academy, who signed him from his first club, Stern Marienfelde, at the age of seven.
Compared to Toni Kroos from a young age, he was entrusted with captaining Hertha's various youth teams while regularly winning Player of the Tournament prizes at competitions around the world.
Getty/Goal
Unsurprisingly, the great and good of the footballing world began to take interest.
Barcelona and Arsenal both made offers for Rhein to continue his footballing education outside of Germany, but the youngster was keen to stay in a city where he could experience the best of both worlds in terms of formal training with Hertha as well as the freedom he enjoyed in the park.
It was not until 2017, at the age of 14, that he was eventually tempted away from Berlin by veteran coach Hermann Gerland, who convinced Rhein that his future would be best served by enrolling at Bayern's brand new youth campus.
"Torben Rhein: Remember the name!" Gerland, AKA 'The Tiger', told a panel discussion at the German Football Museum shortly after securing the youngster's signature, so sure was he of his talent.
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But what is it that distinguishes Rhein from his peers?
"His game intelligence and his two-footed ability are among his greatest qualities," Bayern's Under-23s coach, Holger Seitz, tells Goal and SPOX having recently handed Rhein his debut in the third tier of German football.
"That makes him so unpredictable and difficult to defend with the ball at his feet."
Rhein cites Barca legend Andres Iniesta as his role model, and as such prefers playing as a No.8, though he has also been used as both a No.6 and No.10 at various stages of his academy career.
Since arriving at Bayern, he has returned 18 goals and 10 assists in 52 youth-team appearances across the U17s and U19s, though it is not just the physical side of the game that Rhein has been working on in recent years.
Since the age of 15 he has worked with private trainer Steffen Tepel, who has made his name as a neuro-athletics coach by helping to train the brain so as to boost physical output.
"He is excellent with both feet, and shows great symmetry of movement and technique in his shooting," Tepel (pictured below coaching Rhein) tells Goal and SPOX. "This shows that he is able to balance both hemispheres of the brain.
Steffen Tepel
"This, in turn, enables him to achieve an extraordinary degree of precision in his shot and passing.
"His peripheral vision is very well developed, so he can perceive what is happening around him very well. This gives him the overview, which then allows him the ability to hit strong passes out of difficult situations."
Those abilities were fully on show in Rhein's second apperance for the U23s, as he laid on a superb assist for striker Christopher Scott in March's 2-2 draw with Waldhof Mannheim.
"Playing for the U23s will help him to take further development steps in all areas, especially in the area of counter-pressing," Seitz says of the Fritz Walter silver medal winner, with Rhein ranked below just Bayer Leverkusen starlet Florian Wirtz in terms of German players in his age-group.
That talent continues to be monitored outside of Germany, too, with Chelsea among the clubs to have been linked with Rhein in recent years.
There was a fear at Bayern that the midfielder could even depart this coming summer when his original youth contract expired, but in January it was announced that he has extended his deal through until the summer of 2022, at which point he will hope to be closing in on first-team action.
"We are all very happy that he has decided to continue on our path together," says Seitz. "He certainly also had other sporting opportunities. The fact that he is staying here on campus speaks for the concept that we presented to him."
Rhein certainly has all the tools to succeed at a club of Bayern's stature. If he does, then maybe one day he will be the subject of some street art back in Berlin.
'Grown on rubber', would be a suitable caption.