Borussia Dortmund have been on the decline in recent years.
Jurgen Klopp had great success at the start of the decade as he created one of the best teams in Europe.
The German manager managed to break the dominance of Bayern Munich by winning the Bundesliga back-to-back in 2011/12 and 2012/13.
He also managed to lead Dortmund to the Champions League final in 2013. But Die Borussen have struggled since Klopp's departure in 2015.
Dortmund only managed 55 points last season, which barely secured their place in the Champions League.
However, it could have been so different for the club. Dortmund have had a number of world class players at their disposal in recent years but have failed to keep hold of the very best of them.
But what would their side look like if they didn't sell their best players? We have taken a look and the side definitely has the ability to challenge both in Germany and in Europe.
GK: Roman Bürki
A steady player, the Swiss international has been Dortmund's first-choice goalkeeper for the past three seasons.
LB: Marcel Schmelzer
Schmelzer emerged from Dortmund's youth system in 2008 and has been a key component ever since.
The reliable full-back has made 346 appearances for the club and has represented Germany 16 times.
CB: Mats Hummels
Hummels was one of the world's best defenders at Dortmund and it remains that way.
Dortmund were gutted to have lost Hummels to Bayern Munich for £31.4 million in 2016.
CB: Sokratis Papastathopoulos
The 30-year-old left for Arsenal this summer after making 198 appearances for the club.
He has enjoyed a decent start to life in north London.
RB: Łukasz Piszczek
Now 33 years old, Piszczek remains a reliable player for Dortmund.
He has made 298 appearances and scored 16 times for the club since joining in 2010.
CM: Ilkay Gundogan
Gundogan has had numerous injury problems in his career but he is still one of the best midfielders in the world.
He left Dortmund in 2016 for £20 million and is now excelling under Pep Guardiola at Manchester City.
CM: Henrikh Mkhitaryan
We've put Mkhitaryan in a slightly more defensive role but it would have been harsh on him to leave him out of the side.
He was seriously impressive for Dortmund, scoring 41 times in 140 games.
The Armenian left for Manchester United in 2016 and currently finds himself at Arsenal.
LW: Marco Reus
Reus would have had numerous opportunities to move to a bigger club in the past but has shown great loyalty to Der BVB.
He has had his fair share of injuries in recent times but has still racked up an impressive 98 goals in 206 games for the club.
RW: Ousmane Dembele
Dembele spent just one season in Germany but what a season it was.
The talented youngster scored 10 times in his only campaign at the club before securing a €105 million move to Barcelona.
He seems to have found his feet after a difficult first season in Spain.
ST: Robert Lewandowski
What a player. Lewandowski has been one of the best strikers in the world for the vast majority of this decade.
Like Hummels, Dortmund were very unfortunate to lose him on a free transfer to Bayern Munich.
ST: Pierre-Emerick Aubameyang
What a lethal strike partnership Aubameyang and Lewandowski could have formed.
Unfortunately the two only played together for a season before the Polish striker's departure for Bayern Munich in 2014.
The Gabonese captain netted 141 times in 213 appearances for joining Arsenal earlier this year.
Honourable mentions: Mario Gotze, Ivan Perisic, Axel Witsel
What a team that would be - especially in attack.