#2 The 4-2-3-1 or 4-2-4 formation
Barcelona, once famous for its 4-3-3 style adopted under Frank Rijkaard and then Pep Guardiola slowly stopped using the same pattern - especially in the past couple of years. Apart from the departures of midfield legends Xavi Hernandez and Andres Iniesta from the club, there is another reason for this as well - Sergio Busquets.
The holding midfielder, who has been at his prime form for nearly a decade, hasn't been at his best during the recent past. If Iniesta and Xavi had the responsibility of dominating the game through their passing, Busquets used to be the central link in between them.
But for the first time in years, the Spanish superstar's passing seems a bit too erroneous, with him making many wayward decisions on the ball. Hence, while Busquets remains an important starter in most cases, Valverde will be cautious of this problem and may rightly look to replace the ageing veteran with De Jong, who will be an ideal replacement.
De Jong's ball-holding skills and possession-control abilities have already attracted a lot of attention - even before he has left the Dutch shores.
There may also be cases where Barca is countered by clubs with a tighter defensive backline. In such a case, making runs into the opponents' box can prove a bit too engrossing for the front-three, which is when an additional man up front can be of great help.
Barcelona can achieve that with the 4-2-3-1, or the 4-2-4 as required. From left to right, Dembele, Suarez, and Messi will constitute the front-three while Coutinho will don the role of a centrally attacking midfielder just behind Suarez' line, just like from his days of yore at Liverpool.
Alongside Arthur, Rakitic or Vidal, De Jong can make an impact in the "Busquets role", forming a strong central line of support (refer below figure).