Barcelona made some big strides in the January transfer market.

The Blaugrana announced the signing of Dutch starlet Frenkie de Jong from Ajax, with the elegant midfielder joining the squad in the summer.

De Jong will cost Barca a cool €75m and it was reported that he would pocket a huge salary upon his arrival in Catalonia.

The club don't usually hand younger players enormous wages, but they made an exception with De Jong.

And the reason why may have finally been revealed. As reported by ESPN, Nike will pay a significant amount of De Jong's wages, which was the catalyst in him rejecting Paris Saint-Germain.

Nike sponsor both Barca and De Jong and a source confirmed they will invest a "very important amount of money" in wages - but they won't contribute to the transfer fee.

Executives within the company believe that their investment will be rewarded and have asked the Dutchman to wear 'Frenkie' on the back of his shirt for marketing purposes.

On international duty this week, De Jong also admitted that he asked Ronald Koeman - a former Barca player himself - his advice on the move.

"Yes, I did," the 21-year-old said, per Goal. "Every time I joined up with the national team.

"There's always been rumours of interest, so I wanted to know what Ronald Koeman thought of everything.

"[He said] to go somewhere I get to play regularly. It didn't matter where, as long as I played.

"I'm sure the manager has his preferences, but to him it's most important to gain experience at the highest level."

Barca are also keen on landing De Jong's Ajax and Holland teammate Matthijs de Ligt, with the 19-year-old centre-back also on Juventus' radar.

According to Catalan publication Sport, Barca and Ajax are exploring a 'collaboration' between the two clubs over future transfers.