It comes as no surprise that Borussia Dortmund are this season’s biggest spenders in the Bundesliga, splashing out £65 million on arrivals, contributing to the league’s £406m spent across all 18 teams, with RB Leipzig, Schalke and Stuttgart spending half of BVB’s budget.

But perhaps the team that has impressed the most this window is Bayer Leverkusen. They’ve gone about their business away from the headlines, bolstering their squad in remarkable fashion. It was announced in April that Paulinho would join die Werkself in the summer window – a shrewd signing that adds to an already exciting Leverkusen front line.

The 18-year-old has impressed during pre-season for Heiko Herrlich’s side while the Brazil youth international was awarded with his first start in the DFB Pokal, against CfR Pforzheim. At just £16m, Paulinho’s arrival in Germany seems relatively risk free given the fees many European clubs are shelling out in modern football, with league rivals RB Leipzig just one example, while European clubs such as Atalanta, Fiorentina, Real Betis have done their fair share of business.

Given Leverkusen’s stature and sustainability, there’s no doubting that there was money to spend should Herrlich and sporting director Rudi Völler have opted to do so.

Needing to strengthen at right-back, B04 chose to look in their domestic league. Mitchell Weiser, formerly of Bayern Munich, arrived at the BayArena from Hertha BSC for just £10m, while Leverkusen did well to beat off interest from Premier League clubs. It could signal the end of Benjamin Henrich’s career at the Bundesliga club with AS Monaco interested, but there’s no denying that Weiser poses more of an attacking threat while he’s stronger defensively in an area that proved problematic for Leverkusen last season.

Even with the departure of Bernd Leno to Arsenal, they’ve done well to recruit Lukas Hradecky on a free transfer from Eintracht Frankfurt. The Finland international cemented himself as one of the Bundesliga’s best goalkeepers last campaign with the 28-year-old showing time and time again that he can take Leno’s place.

But perhaps what is more remarkable from Bayer Leverkusen’s summer transfer window is their ability to retain their best players. Julian Brandt was linked heavily with a move to Bayern Munich and Liverpool before signing a contract extension prior to jetting off to Russia with Germany for the World Cup.

Granted, it may be a ploy to get more money from a potential suitor later, but to have Brandt remain at the club for at least the next season, if not until 2021, could prove crucial for Leverkusen as they look for a return to the Champions League.

If Brandt wasn’t enough, Kai Havertz extended his contract with the Bundesliga club last summer while Herrlich & Co. remain confident the 19-year-old will remain in Leverkusen for at least the next couple of years. At such a young age, Havertz has already shown what he’s capable of, becoming B04’s youngest player and goal scorer in the top flight.

And lastly, the Bundesliga club announced on Sunday that Leon Bailey has agreed an extension on his contract, signing until 2023. It’s known that the 21-year-old has garnered interest from Europe’s top clubs but with a preference to play for Germany in the future, Bailey has opted to remain at Bayer Leverkusen, where he believes they can challenge for the title.

“We want to play for the title,” Bailey told Kicker. “Bayern Munich are for me one of the three strongest teams in the world, but in football you never know. We have to be focused and then, with our qualities, we can achieve a lot.”

Following his extension, the wunderkind expressed his appreciation for the club and how settled he feels in Leverkusen.

“This contract extension is a show of appreciation for the support I’ve had and I’ve always said how happy I feel here in Leverkusen,” Bailey told the club’s website. “We can achieve a lot with this young team. My goal is to repay the trust shown in me with good performances and consistent development.

“We want to play for the title. Bayern Munich are for me one of the three strongest teams in the world, but in football you never know. We have to be focused and then, with our qualities, we can achieve a lot.”

So, it just goes to show that you don’t need to spend a sum of money to improve a team. Bayer Leverkusen have built on last season’s team with continuity and the addition of strength in depth as well as a phenomenal talent that could well make Germany his stage.

By Daniel Pinder