With the pre-match build up dominated by Newcastle's off-field changes, the club's new PIF owners were served up a stark reminder of the issues on the pitch as Steve Bruce's 1000th game as a manager ended in defeat.
Callum Wilson's second-minute header buoyed an already rampant home crowd, but Tottenham hit back through Tanguy Ndombele before Harry Kane scored his first Premier League goal of the season.
A fan was taken to hospital after an incident late in the first half, which led to a defibrillator being called for and the suspension of play. When it restarted, Kane turned provider for Son Heung-min.
Jonjo Shelvey's red card seemed to erase any Newcastle hopes, only for Eric Dier's late own goal to worry Spurs, but it was ultimately not enough to inspire a comeback.
Newcastle's pre-match elation swiftly carried onto the pitch. Only one minute and 47 seconds had passed when Wilson got ahead of his marker to head in Javier Manquillo's cross.
Yet a blistering following 10 minutes failed to produce another Newcastle goal and, after Lucas Moura fired a warning shot, Spurs drew level through Ndombele's superb, curling strike into the right-hand side of the goal.
Spurs' turnaround was complete five minutes later as Kane darted onto Pierre-Emile Hojbjerg's lofted pass and finished deftly over Darlow. The goal was initially disallowed for offside, but VAR spotted Manquillo's failure to step up in time.
Lucas rattled the woodwork as Spurs searched for a third, though play was then suspended due to a medical emergency in the crowd.
Spurs picked up where they left off following a long delay – Kane squaring for Son to make it 3-1.
Devoid of ideas going forward, Newcastle's day turned from bad to worse in the 83rd minute.
Shelvey, brought on as a 60th-minute substitute, brought down Sergio Reguilon, duly receiving his second yellow card.
Newcastle was handed hope by Dier bundling into his own net, though Spurs held firm to condemn its host to another damaging defeat.