The Lilywhites made a record-breaking start to life under the Celtic treble winner, who collected an unprecedented 26 points from his first 10 Premier League matches in charge of the North London giants.
However, Spurs' short-lived title charge quickly petered out, and come the end of the season, their hopes of returning to the Champions League after a one-season absence were also dead in the water.
Nevertheless, Postecoglou - who repeatedly affirmed that finishing fourth was not his ultimate goal - led Spurs back onto the continent with a fifth-placed Premier League ranking, good enough for a path into the Europa League.
Focus now shifts towards a major summer overhaul in the transfer market for Tottenham, who have already confirmed the departures of Ivan Perisic, Eric Dier, Japhet Tanganga and Ryan Sessegnon on free transfers.
Richarlison headlines possible Tottenham exits
A new striker, winger and centre-back are believed to be of the utmost importance to Postecoglou this summer, and as many as 10 players under contract could be allowed to seek pastures new after being deemed surplus to requirements.
Should Spurs manage to shift all of them for at least their market value - as calculated by Transfermarkt - the Lilywhites could find themselves a staggering £131.6m better off as Postecoglou aims to stamp his authority on the squad.
Of the 10-strong list who could be on the way out, inconsistent striker Richarlison is by far and away the most valuable at £32.3m, and Tottenham are said to be prepared to listen to offers for the former Everton and Watford attacker.
Fellow attacker Bryan Gil (£11.9m) could also depart permanently, having been sent out on loan a couple of times while failing to play his way into Postecoglou's good books, suggesting that a permanent move back to Spain could be on the cards.
As many as four midfielders could head for the exit door too, including all-time record signing Tanguy Ndombele, now only valued at £6.8m after Tottenham shelled out £52.7m to sign him from Lyon five years ago.
Pierre-Emile Hojbjerg, Emerson Royal on transfer list
Giovani Lo Celso (£13.6m) surprisingly stayed last summer but is also on the chopping block after only playing a peripheral role last season, as is the home-grown Oliver Skipp (£12.7m), now open to a move away as well.
Pierre-Emile Hojbjerg (£15.3m) was linked with a move away in January amid reports of interest from Serie A clubs, and having also fallen behind Yves Bissouma and Pape Sarr in the food chain, his time at Tottenham is nearing an end too.
A trio of full-backs also have no future at Tottenham under Postecoglou, who sanctioned two loan moves to Manchester United and Brentford for Sergio Reguilon (£10.2m) during the 2023-24 season.
Djed Spence (£6.8m) is also discussing a permanent move to Italian outfit Genoa, whose Serie A rivals are apparently among the clubs interested in Emerson Royal (£15.3m), also watched by Bayern Munich and Saudi Pro League teams.
Finally, the £6.8m-rated Joe Rodon should end his unsuccessful time at Tottenham this summer after a productive Leeds United loan, and Spurs have reportedly triggered an extension in his contract to ensure that he will not leave for free.