Luiz had joined the Man in the City three years ago from Vasco da Gama, but a failure then for the purchase of a UK work permit forced two-season loan move to Girona, Spain.
A buyout clause has been inserted in the transfer, allowing the City to redeem the young Brazilian for a preset amount in the future.
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Under this agreement, if they wish to trigger the buyout clause in the future, there would be a contractual obligation for Luiz to return to Eastlands.
The details of this clause have not been released – but the price is much higher than that paid by the buying club, and develops over time.
Therefore, if the reports of £15 million to be paid by the Villa are true, it may be the City’s buy-back clause is set at £25million this summer and £30million the following season.
It’s all conjectures and assumptions, but it is logical based on cases involving a buy-back clause.
However, there are, at the same time, any obligation for the City to trigger the clause – and indeed, it has been suggested that the clubs could work together to remove the clause of a contract player in the future.
This means Luiz could be a key component to Villa Park for years to come, in effect, if the transfer is finalized and the City choose not to exercise the clause.
While such clauses are popular abroad, it is rare to see them in the Premier League – though a trend seems to emerge.
Manchester City themselves benefited from the terms of the clause in 2019, in resigning their former left-back Angelino PSV Eindhoven, one year after his departure for the netherlands.
Thus, while the strategy has been a success for some clubs in recent seasons, those on the receiving end – as PSV were – may the curse their luck.
Angelino had just been named Eredivisie Talent of the Year for 2018/19, as well as in the Eredivisie Team of the Year for the second consecutive season.
Therefore, his true market value was probably much more than the reported £5.3 million City paid to bring him back to Manchester.
In the Premier League, Chelsea have used the same tactic, to put a buy-back conditions on the sales of several young players from the academy, who has left the club, including Nathan Ake and Bertrand Traoré.
This underlines the increase of the popularity of the clause of redemption in recent seasons.
A recent example is the Barcelona to be able to resign from their La Masia graduate Gerard Deulofeu of Everton in 2017 for a nominal amount, triggering his buyout clause.
They were then moved to the winger at Watford a year later for a profit.
Real Madrid has done much better with their Castilla graduate Alvaro Morata.
The Spanish forward has gone to Juventus for £18m in 2014 – with a clause of redemption.
Real Madrid has activated this in 2016 – for a £27m – before his form in their double winning season 2016/17 earned him a £65 million move to Chelsea.