Top 10 most profitable transfers of all time

#4 Ousmane Dembele - Borussia Dortmund to FC Barcelona

Barcelona v Espanyol - La Liga

A little more than 2 years ago, Ousmane Dembele had just enjoyed his breakout season in Ligue 1, one of the cogs of a Rennes team that finished just outside the European spots. The 20-year-old is now one of the most expensive players of all time, and it has been a whirlwind two-and-a-half seasons since.

Borussia Dortmund are another of those clubs that tend to sell well, but they surely could never have anticipated that they would make such a huge profit on Dembele in just 1 year. €15 million brought them an excellent season, as well as a massive profit that could bankroll the club's signings for years to come.

Currently, given Dembele's injury upon arrival, Barcelona are considered to have overpaid. However, Dembele could quite conceivably become one of the best players in the world in the future, and €105 million could eventually be seen as a fair fee.

Fee Paid: €15m

Fee Sold: €105m

Profit: €90m