But such spending has raised questions about whether clubs would be able to comply with the Uefa financial fair play regulations.

BBC: Uefa warns clubs after deadline-day transfer spree

With costs escalating and UEFA's Financial Fair Play regulations which limit a club's annual losses on the horizon, it makes sense to invest in youth.

WSJ: Youth Academies: Soccer's Nature vs. Nurture Debate

There's another major side effect to third-party ownership: Its impact on the new Financial Fair Play regulations that limit the losses clubs wishing to play in lucrative European competition can sustain.

WSJ: Third-Party Ownership: How to Stud a Soccer Player