It is clear that Nuno's counter-attacking style differs largely from Postecoglou's approach, so what does this mean for Forest?
Forest's transfer business this summer appears to have been done with an eye on becoming a more technical, ball-dominant side.
Interestingly, James McAtee, Douglas Luiz and Oleksandr Zinchenko are all players who have all developed at Manchester City, highlighting the change in intent.
Big-money signing Omari Hutchinson and fellow Chelsea graduate Calum Hudson-Odoi might also enjoy playing in a way that ensures they keep the ball more, with licence to create.
Questions arise when looking at the out-of-possession differences between both managers.
Nuno has often held the lowest defensive line in the league across his various clubs, with Postecoglou playing the highest defensive line at Spurs.
If this drastic change is implemented immediately, some of Forest's strongest defenders, who thrive on defending their box, may not be maximised. The defensively astute Nikola Milenkovic comes to mind here.
The difference in system raises questions for somebody like Ola Aina, who had an incredible campaign last season playing as a touchline wing-back, a role that differs from the inverted full-back demands asked of a Postecoglou full-back.
Postecoglou has been reluctant to alter his system, but there was a level of pragmatism seen in Spurs' Europa League win.
Tottenham were happier to defend their own box for large periods of time, leading to success against Eintracht Frankfurt and United.
Without a pre-season, and coming into a club that has been built on a counter-attacking, five-at-the-back style, adopting an approach more in line with Spurs' knockout games might be a sensible thing to do early in Postecoglou's tenure.