Notable players from Bayern Munich, Manchester United, and Liverpool were among the priciest transfers during the 2015 summer window.
Splurging a lot of money is certainly not a guarantee of success, as illustrated by this list, which shows that only a few of these transfers turned out well.
We have looked back at the 10 priciest transfers from the 2015 summer window and evaluated their performance over time.
10. Roberto Firmino
Paying approximately £29 million, it's fair to say that Liverpool have received excellent value from Firmino.
When he first joined, the Brazilian became Liverpool's second most costly acquisition, following only Andy Carroll, who was signed for £35 million.
Brendan Rodgers was the one who brought him in, but it was Jurgen Klopp who unlocked Firmino's abilities.
Operating as a false-nine alongside Sadio Mane and Mohamed Salah, the Brazilian was unstoppable during his prime years at Anfield.
He found the net 111 times and provided 76 assists in 362 matches with the team. It's fair to say he was a valuable investment.
9. Arturo Vidal
Following a number of successful years at Juventus, Bayern Munich acquired the Chilean player for a transfer fee approximately £32 million.
The central player spent three years in Germany and secured six honors with the team, including three straight league championships.
After departing the club in 2018 to sign with Barcelona, Bayern incurred a financial loss on his transfer, but considering the strong years he contributed, it was still viewed as a beneficial move.
At 38 years old, he continues to play professionally, currently representing Colo-Colo in his home country.
8. Christian Benteke
Following several strong years at Aston Villa, Benteke moved to Liverpool in a transfer worth £32.5 million.
He found the net 10 times across all tournaments during his only season at Anfield, after which he was transferred to Crystal Palace for a fee of £32 million in 2016.
Since things hadn't quite worked out for the Belgian at Anfield, the club was satisfied to nearly break even on the transfer.
Notably, he outperformed Lionel Messi to claim the MLS Golden Boot in the previous season, netting 23 goals in 30 games with DC United.
7. Nicolas Otamendi
During the last season of Manuel Pellegrini at Manchester City, the team made a significant impact in the transfer window by acquiring several well-known players.
Among their summer acquisitions was Otamendi, who moved from Benfica in a transfer valued at approximately £33 million.
In the end, his tenure in Manchester was somewhat of a mixed experience. There were moments when he appeared as solid as a brick wall, and other times when he seemed like a potential disaster.
Over the course of his five-year period at the club, he secured nine titles and played more than 200 matches, which is a solid record.
6. Paulo Dybala
Joined by Juventus for a transfer fee that could reach approximately £34.5 million with additional clauses, Dybala appeared to be a genuine talent in 2015.
His smooth ball control, combined with a powerful left foot, made him nearly impossible to stop during his prime.
The Argentine striker spent seven years with Juventus, netting 115 goals for the team and securing 11 titles during his tenure.
He continues to be active in Serie A today, but now with Roma, who are Juventus' competitors.
5. Julian Draxler
Having been associated with clubs such as Arsenal and Juventus, Draxler ultimately moved to Wolfsburg in 2015 through a £35.5 million transfer.
The German midfielder was seen as one of the top talents in Europe during his initial time at Schalke, but his transfer to Wolfsburg did not unfold as expected.
Within a year of joining the club, Draxler expressed his intention to depart in 2016, and his request was ultimately approved in January 2017, as he moved to PSG.
He was able to accumulate a significant amount of silverware during his six-year period in Paris, yet he never truly managed to become a regular starter.
Currently 31 years old, he competes in the Qatar Stars League with Al Ahli.
4. Angel Di Maria
After a disappointing period in Manchester, PSG acquired the Argentine winger for approximately £44 million.
In the end, it turned out to be a beneficial agreement for the French club, and Di Maria experienced some of his most productive years competing in Ligue 1.
He found the net 92 times and set up 120 goals in 295 matches, contributing a goal every 100.1 minutes with the team.
Having served for seven years, he departed in 2022 to sign with Juventus and, at 37 years old, currently plays for Rosario Central in Argentina.
READ: Angel Di Maria's Man Utd ordeal, as quoted: 'Talented but a total fool'
3. Anthony Martial
Manchester United paid an initial fee of £36 million to acquire Martial from Monaco, but this amount ultimately increased to £44.7 million when additional clauses were included.
In 2015, Martial was seen as one of Europe's most exciting forwards, and he quickly made an impact at United, netting 17 goals in his first season.
Nevertheless, injuries and various other challenges prevented the French player from achieving his maximum potential at United.
He definitely experienced some highly productive periods, but considering the high expectations when he first arrived, Martial never truly met that level of anticipation.
Having spent nine years at the club, he departed in 2024 after netting 90 goals across 317 matches. At just 29 years old, he is currently playing for AEK Athens in Greece.
2. Raheem Sterling
At the moment of the transfer, Sterling was the most costly English player in history, moving to Man City with a deal valued at £49 million.
Although Liverpool supporters were not happy about his departure back then, Sterling believes the move was justified, considering the years of success he experienced in Manchester.
The forward netted 131 goals over his seven-year tenure at the Etihad and secured 11 honors, among them four league championships.
His career after City hasn't quite shone as brightly, but he will always be cherished on the blue side of Manchester.
1. Kevin De Bruyne
The priciest move during the 2015 summer window was undoubtedly the finest.
Having made a significant impact in the Bundesliga, Man City lured him back to the Premier League with a transfer fee of £54 million.
Back then, it appeared to be a significant sum, and many analysts expressed surprise at the deal. Nevertheless, KDB soon convinced the skeptics.
After a decade of dedication with Manchester City, it's fair to say that De Bruyne is considered one of the top midfielders in Premier League history.
He registered 285 goal-related actions in 422 matches across all tournaments, securing 19 titles in the process.
"It's nearly impossible to find a substitute for a player like this," Pep Guardiola remarked when De Bruyne joined Napoli.
It's not only about the performance, but also about what he represents to the hearts of our fans over many years. The achievements we've reached belong to the players.
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