THE KLOPPEL-GANGER: HOW HE WON BACK TO BACK TITLES AT DORTMUND

Having impressed at Mainz, Klopp was attracting interest from the likes of Bayern Munich when Dortmund signed him up in 2008, just after they finished 13th in the Bundesliga.

In his first season they finished sixth and he signed Mats Hummels for a steal at £3.5million.

He then cleared out dead wood and brought in Kevin-Prince Boateng and Damir Vrancic. Signed striker Robert Lewandowski as a 22-year-old in 2010 for £4m, as well as bringing in Shinji Kagawa.

Lewandowski marked his debut season in 2010-11 with eight league goals but it was the 16 from Lucas Barrios that spearheaded the charge to a first title since 2002.

Forced to sell his best player in Nuri Sahin to Real Madrid, he simply went out and unearthed two diamonds in 20-year-old Ilkay Gundogan and 22-year-old Ivan Perisic, for £4m each.

Lewandowski scored 22 league goals that season, Kagawa got 13, Perisic chipped in with seven and youngster Gundogan made a name for himself playing 28 Bundesliga games as they won back-to-back championships.