Newcastle midfielder Hatem Ben Arfa kept his nerve to score the late penalty that handed Andre Villas-Boas a 2-1 defeat in his first match as Tottenham manager on Saturday.
After a dismal eight-month spell at Chelsea ended with his sacking last season, Villas-Boas is back in the Premier League with a point to prove.
But the young Portuguese coach, a surprise appointment following Harry Redknapp's dismissal at the end of last season, will need to get more from his players than they delivered in an inconsistent display at St James' Park.
Senegal striker Demba Ba put Newcastle ahead with a superb goal early in the second half and, although Jermain Defoe grabbed an equaliser, it was France international Ben Arfa who won and then converted the decisive penalty with 10 minutes remaining.
While Villas-Boas returns to north London with plenty of work to do, it was business as usual for Newcastle boss Alan Pardew.
Pardew presided over a remarkable campaign for the Magpies last season as they defied predictions of a relegation battle to challenge for the place in the Champions League.
Newcastle eventually finished fifth and on the evidence of this impressive effort another high finish is well within their grasp.
Villas-Boas's side had looked sharper in the first half and were desperately unlucky not to take some kind of lead into the half-time break after both Defoe and Gareth Bale clattered shots against the woodwork.
Defoe was sent through by a neat ball from Jake Livermore in the 33rd minute but fired against the base of Tim Krul's right-hand post, and three minutes later Bale headed powerfully against the bar from an Aaron Lennon cross.
While Pardew started with his new signings Vurnon Anita and Romain Amalfitano on the bench, Villas-Boas gave Gylfi Sigurdsson his debut and the ex-Swansea midfielder was at the heart of most of the visitors' attacking moves.
But the home side snatched the lead in the 54th minute when Danny Simpson's high ball into the box was only half headed clear by Kyle Walker, and Ba responded with a curling shot high into the net from the corner of the box.
Benoit Assou-Ekotto drilled a long-range effort which was parried by Krul before Pardew was sent to the stands on the hour for over-protesting a touchline incident.
Newcastle made their first change in the 70th minute, new boy Anita replacing Yohan Cabaye, and at that point the Magpies were in control.
Spurs grabbed their equaliser in the 76th minute when Lennon crossed into a crowded box and Defoe wriggled free to fire past Krul at the second attempt after his initial header had been parried by the keeper.
However, Spurs were level for only four minutes before Rafael Van der Vaart was penalised for tripping Ben Arfa in the penalty area and the Frenchman picked himself up to send Brad Friedel the wrong way from the spot.