Lisandro Martinez spoke with Donny van de Beek before joining Manchester United.
The Argentina defender completed a £46.8m switch from Ajax to Old Trafford on Thursday.
Van de Beek is a fellow Ajax alumni and the pair spoke about life with the Red Devils.
He told MUTV: "Well, I spoke with Donny when everything was done, yeah. I asked something to Donny. We spoke a little bit about Manchester, so yeah."
Asked about ten Hag, Martinez added: "Well, I was with him three years at Ajax and I know his style of playing.
"With him, I improved a lot to be honest. He's here in Manchester now, so again the opportunity was there and for sure he's very important in my career.
"[He's] very intense, for sure. Good football. Winning mentality, you know? That's the most important, yeah. Every player needs to have things clear. I think he's very clear also so I think with him every day you can learn and then in the game you can understand also fully – tactics and everything."
