Gray left Leeds United for Spurs earlier this summer.
Of his first meeting with Postecoglou, he recalled to Football.London: "It was just really positive and most of it was football, but he was getting to know what I was like as a person.
"Hopefully I came across really well but it’s a massive factor that the manager's here and I've been following him for a while, since he was at Celtic and one of my U21 managers went to the Australian league so even since then I’ve been following him so, yeah, he’s a massive factor."
The Gray family have connections with Celtic, which was another appeal with Postecoglou a former Hoops manager.
"Obviously I’ve got a Leeds family and I support them too, but yeah my grandad and dad played for Scotland and supported Celtic.
"When Ange was there I enjoyed watching them and I still do now," Gray added.
