The outstanding Dominic Solanke, proving once more what a fine signing he has been since his £65m arrival from Bournemouth, scored twice with a Dejan Kulusevski goal sandwiched in between to put Spurs in total control.
This being Spurs, however, if something is worth doing it is worth over-doing. And so it proved.
Forster only found Bruno Fernandes with a pass from his goalline, the Manchester United captain setting up substitute Joshua Zirkzee after 63 minutes.
The keeper then made matters worse seven minutes later when hesitation and a poor touch saw him crash a clearance off Amad Diallo into the net.
Cue chaos. Cue the old “Spursy” jibes being dusted off.
The latest sideswipe is the label “Dr. Spurs” – providing a cure for teams who have not won before in the Premier League season, as applied to Crystal Palace and Ipswich Town.
Spurs can make themselves an easy target at times but they are still one of the hottest tickets around when it comes to putting on a show – for good and bad – under Postecoglou.
They eventually pulled themselves around here, leaving Postecoglou still with the chance to fulfil his boast that he always wins a trophy in his second season.
Postecoglou’s commitment to attack and entertainment is laudable and it will be a personal triumph if he finally ends the long wait for Spurs to win a trophy, although they face a tough two-leg semi-final against Liverpool, especially with the second game at Anfield.