By North-west correspondent Alex Stevens

Eliaquim Mangala cost Manchester City a staggering £41.9million, leaked transfer documents reveal.

The website Football Leaks has published what appears to be an authentic transfer agreement between City and Porto of the defender’s move in 2014.

It reveals that the Premier League club paid far in exceed of the £32million they originally claimed they had paid for the France international.

Mangala’s fee comfortably trumps the £33million Manchester United paid for Rio Ferdinand in 2002 to make him the most expensive defender in Premier League history.

According to the document, which appeared online on Wednesday, Porto only owned 56.67 percent of Mangala’s economic rights.

The remainder was split between The Doyen Sports Investment Limited, who owned 33.33 percent, with another 10 percent belonging to an Austrian marketing company.

City had to pay £23.4million for Porto’s share alone, meaning the remainder of the deal took the total to £41.9million.

There were suggestions the defender was offered to Valencia on a two-year loan deal as part of the agreement to bring Nicolas Otamendi to the Etihad in August – a move the player rejected.

The Mangala leak follows the release earlier this week in which it was revealed how much Manchester United paid Monaco for Anthony Martial, including details of three performance-related clauses.