In an interview for 'Quan s'apaguen els llums', Van Gaal talked about the difficulties Barcelona has been experiencing since the start of the season, along with Frenkie de Jong's difficulties adapting to the team.
The Dutch midfielder is still a long way from the level he showed at Ajax last season, and now the former coach came up with an original idea.
"He has the foresight to defend forward in good times. I'm not the Barça coach, but I think Rakitic and Arthur can play as well as De Jong in midfield. Barça could improve their central defensive duo by putting De Jong in," said Van Gaal.
"If there's one club that should have bought Matthijs from Ligt, it's Barcelona. And with Busquets in the squad, it's De Jong who should have gone to Juventus," the Dutchman added.
"De Jong is playing very well if we take into account that he's a 22-year-old player who has moved to a foreign club, to a different culture. They paid a lot for him, and that puts pressure on him," he concluded.