It was heartwarming – and not just the part with Jakub Blaszczykowski, Lukasz Piszczek and Nuri Sahin playing on the Signal Iduna Park pitch against a hundred young children, which has smothered social media in the last week. The farewell match that filled international weekend didn’t just allow Borussia Dortmund to pay homage to their two Polish stalwarts, but to a whole generation whose achievements grow in stature with every passing year.

They were all there for what has become known as Tschüssikowski; Lucas Barrios, Kevin Grosskreutz, Marcel Schmelzer and the most important of them all. Jürgen Klopp was back coaching at Westfalen, the famous “Pöhler” (local slang roughly meaning “street baller”) cap atop his head. A day of celebration for Blaszczykowski and Piszczek reminded everybody what BVB had achieved in 2011 and 2012, only a handful of years on from financial near-ruin, with little money by elite-level standards and little experience of mixing it with the top bracket. The excitement that Klopp and his young players brought here in those years was palpable all over again.

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For the first game back after the international pause, it felt like the parameters of time had been distorted. The Bundesliga leaders – albeit overachieving Heidenheim – were their guests for Friday-night fare. And coach Sahin’s Dortmund didn’t play like the ponderous Dortmund of recent years. They played with a tempo and purpose more similar to Klopp’s Dortmund.

“Did the cult coach leave his match plan in Sahin’s office after the legends game last Saturday?” Bild’s Michael Makus asked. There was certainly a lingering euphoria from last weekend’s celebrations as BVB raced into a two-goal lead inside the first 20 minutes and threatened to bury Heidenheim. Even after the concession of a cheap goal to Marvin Pieringer that reduced the deficit, Dortmund were straight back on the horse. Two minutes and four seconds after his header the home side restored their two-goal lead with the minimum of fuss, Karim Adeyemi sweeping home Julian Ryerson’s pass after Serhou Guirassy’s smart dummy. It was the sort of football – incisive, bright and thrilling – for which these supporters have yearned.

For if Klopp’s return, even in exhibition conditions, underlined one thing, it was not how much he is still loved. We knew that. It was how much he is still missed (and, to be honest, we probably knew that too). It was one of the things that made Thomas Tuchel, for all his excellence, never fully accepted here. The same shortcomings, that lack of real connection with the culture, have hampered other coaches who in terms of aptitude were good enough for the job: Lucien Favre, Marco Rose. Edin Terzic was so much of what the club wanted – someone who felt BVB in his bones, who watched from the terraces as Klopp’s team won a glorious double in 2012 – and they were desperate for him to succeed but there was a lack of tactical detail that undermined progress. Some of the visceral thrills under Terzic that, in a way, recalled Klopp’s heyday – the Champions League wins at Signal Iduna Park against Atlético Madrid and Paris Saint-Germain on the way to last season’s final – were not frequent enough. Something had to give.

As BVB prepare for their re-entry into the Champions League with a game at Club Brugge, Sahin’s legacy is equally a blessing and a curse. On a night like this the faithful are reminded why he was the chosen one, the intensity he has worked so hard to instil in training clear; a verve so seductive that the second-half struggles, Pieringer struck again via a penalty to bring the score back to 3-2 – can almost be overlooked. There was, though a sense that Dortmund’s fortitude to hunker down and show the other side to their game was of great satisfaction to Sahin and captain Emre Can, with the latter scoring a late penalty to complete a 4-2 win. “You think about last year,” said Can, recalling Heidenheim coming from 2-0 down to take a point in the same fixture at a similar stage last year, “but we dealt with it well.”

Sahin is not just any bright young coach or venerated former player. He was there when Klopp snared his first Bundesliga title in 2011; in fact it is understating it to say he was just there. At 22 he was Klopp’s brain on the pitch, directing operations from deep. As he stood on the balcony at Borsigplatz on crutches in May 2011 with the city celebrating, Sahin already knew (along with Klopp) that it was his goodbye, with an agreed move to Real Madrid yet to be announced to the public.

Having been part of a golden era, much is expected of Sahin. He may be loved, but he also brings the baggage of expectation. Local and national media commentators alike made it clear in the week leading up to Heidenheim’s visit that this was the time for us to see Sahin’s vision of football, that there needed to be on-pitch substance to match the sheen and nostalgia – after two Bundesliga games (three competitive games overall if we count the first round of the Pokal). The new coach comes with heritage but also with immediate demands on him.

Dortmund 4-2 Heidenheim, Holstein Kiel 1-6 Bayern Munich, Wolfsburg 1-2 Eintracht, Freiburg 2-1 Bochum, Leipzig 0-0 Union Berlin, Mönchengladbach 1-3 Stuttgart, Hoffenheim 1-4 Bayer Leverjusen

His ability to get in the heads of his players is already clear, helped by the assimilation period when he was Terzic’s assistant for the first six months of the year. Adeyemi, a player who has promised plentifully and delivered modestly since arriving from Red Bull Salzburg two years ago, appears to be one. His brace took him to seven goals in 10 days after his fruitful international window with Germany’s under-21s. “Nuri has now trusted me and made it clear what he wants from me,” he said, “and I gave him that.”

Sahin does also have significant resources as underlined by Guirassy’s belated debut – Stuttgart’s goal machine from last season didn’t score but was fully involved, and hints at being the sort of all-consuming presence at No 9 that the club have lacked in the decade since Robert Lewandowski left. The Guinean’s presence is a reminder that Sahin is caught between feelings of understanding and instant expectation – something that Klopp’s brief return only accentuated.

Talking points

• Harry Kane’s fitness had been a cause for concern after his wan performances at Euro 2024, but the England captain really clicked into gear with a hat-trick in Saturday’s 6-1 win at Holstein Kiel (Michael Olise also managed his first goal for the club). Less happy news was Sacha Boey tearing a meniscus, which will keep him out for several weeks.

• On the other side, it was underlined what a struggle the promoted sides have ahead of them. They are yet to register a point between them though St Pauli, who lost 3-1 at Augsburg, threatened to take a draw for much of the second half. Bochum, who avoided the drop by a whisker in the relegation playoff, are also pointless after going down 2-1 at Freiburg.

• Leverkusen recovered from their defeat last time out by trouncing Hoffenheim 4-1, aided by a high home defensive line that would have given Ange Postecoglou a nosebleed. Victor Boniface scored twice in the week that an Amazon Prime series on last season’s extraordinary run hit television screens.