Tottenham had two players sent off in a chaotic game
It is hard to imagine the action in Theatreland matched the dramatic production his side staged alongside Chelsea on an utterly chaotic night in north London.
The fatalistic Tottenham fans who viewed their superb start to the season as too good to be true had their worst fears realised in this a crazy, controversial 4-1 defeat.
No-one can accuse Spurs or Postecoglou of doing things by halves. Not after this.
This was the first time things have really gone seriously wrong for Spurs this season - and they went wrong in the most spectacular fashion in one of the most mind-boggling Premier League games of recent memory.
Spurs fans rolled up the High Road buoyed by the optimism and positivity brought by Postecoglou, knowing victory would put them back on top of the Premier League.
Instead, the wreckage of ill-discipline, red cards, injuries to key players and a painful loss with nine men piled around Postecoglou's feet like rubble.
It leaves the Australian, who has made such an outstanding start since moving to Spurs from Celtic, facing the biggest challenge of his short time in north London.
The infamous Battle Of the Bridge between these two sides in 2016 was brought to mind, especially in a wild first half lasting nearly an hour, and it is Spurs and Postecoglou who have been left counting the cost.
In that period alone, four goals were disallowed, Spurs defender Cristian Romero was sent off and conceded a penalty, and Micky van de Ven and James Maddison went off injured.
It all started so well when Dejan Kulusevski's deflected shot put Spurs ahead after six minutes but it went into reverse at alarming speed from the moment Cristian Romero returned to his old reckless ways.
The Argentine was fortunate to escape a sending off for kicking out at Levi Colwill but could not resist following through on international team-mate Enzo Fernandez, picking up a red card and allowing Cole Palmer to equalise from the spot.
Spurs' night went rapidly downhill from then on as Van de Ven, one of the Premier League players of the season after his arrival from Wolfsburg, collapsed clutching his hamstring as he raced back to halt a Chelsea attack, before Maddison also went off after appearing to pick up an ankle injury.
Van de Ven and Maddison are very near the top of players Postecoglou could not afford to lose. The Dutchman's injury looked serious while Spurs will hope Maddison is not sidelined for too long.
Chelsea have now won three of their last five Premier League games
Like Romero, Destiny Udogie was lucky to escape a red card for an early lunge on Raheem Sterling but a rash, late dive into another tackle early in the second half on the same player left referee Oliver no option but to send him off.
This meant that, after just over an hour of play, only three of the outfield players who started the match for Spurs were still out there.
Postecoglou gambled on maintaining a high line even with nine men. It would have been miraculous had it survived intact. Sterling and Nicolas Jackson found a way through with only 15 minutes left, the striker helping himself to a hat-trick as Spurs ran out of steam.
If there is any good Postecoglou can take from a very bad night, it is the spirit shown by Spurs as they tried to hold on, backed by a vociferous home crowd who appreciated the character shown in difficult circumstances.
Keeper Guglielmo Vicario was heroic, racing from his goal on several occasions to act as an emergency sweeper, but in the end even his resistance was broken.
Spurs left the pitch after the final whistle to rousing applause but this was a chastening experience which leaves Postecoglou with his first real session of problem solving.
He will await medical bulletins on his injured duo while also knowing Romero faces a three-match ban - made more significant by Van de Ven's injury - while Udogie will miss one game.
Spurs have a visit to Wolverhampton Wanderers coming up, followed by a home game against Aston Villa before a trip to face league leaders Manchester City at Etihad Stadium.
Postecoglou's calm demeanour has won him a host of admirers at Spurs and beyond this season and the time-honoured warning about bumps in the road had been mentioned even before it all went off the rails here.
The ordered, pragmatic - but always positive - approach which has served him so well will be required because a bump in the road is one thing, but being faced with a mountain of unexpected problems is another.
Nobody has ever suggested managing Spurs is as easy as Postecoglou has made it look, and this almost surreal night delivered compelling proof.
-- Courtesy of BBC Sport