Steve Bruce silenced the doubters as Newcastle stunned Tottenham to hand their manager a first win in charge after more VAR drama.
Taking over from Rafael Benitez in the summer, Bruce has already found himself under pressure after losing his first two games, but Joelinton's first goal for the club earned a memorable three points at the Tottenham Hotspur Stadium.
They were helped by a poor performance from Spurs, who rarely threatened to break down a dogged Newcastle defence and undid all the good work of last week's draw at champions Manchester City.
That point was as a result of VAR intervention, where Gabriel Jesus' last-gasp goal was ruled out, but they did not get help from the technology this week after the decision-review system ruled not to award a penalty when Harry Kane had tumbled under a challenge from Jamaal Lascelles.
It did little to lift the mood at Spurs, one which has been exacerbated by the situation of Christian Eriksen, who was left on the bench amid uncertainty surrounding his future ahead of the European transfer window shutting next week.
Newcastle will not care too much about that, though, as they got their season up and running in style.
Not many people would have given them much hope beforehand as Spurs were heavy favourites, but that was not accounting for their chronic problem of making bad starts to games.
They had plenty of the ball, but, with Eriksen on the bench, had no way of breaking down a 10-man Newcastle wall and it was the visitors who instead found gaping holes at the other end.
One of them should have led to an opener but Sean Longstaff opted to shoot when he had two men free in the box and Hugo Lloris tipped over.
Spurs did not get away with the next one, though, and they fell behind in the 27th minute as Davinson Sanchez was caught playing the offside trap, allowing Joelinton to latch on to substitute Christian Atsu's inch-perfect ball and rifle home his first goal for the club.
It was the third time Spurs have fallen behind this season and 10th in the last 12 games - an issue Pochettino will have to address.
Finding themselves a goal down against a side who came to defend led to an inevitable period of frustration as the hosts try to find a way back into the game.
Their best chance came in the 32nd minute as Kyle Walker-Peters did well down the right and stood a cross up for Son Heung-min, whose volley was well saved by Martin Dubravka while Lucas Moura spurned a good chance with the final kick of the first half, putting a shot wide from Kane's cross.
The second half did not get much better as Newcastle remained compact and defended bravely and Spurs found it impossible to create any danger.
For the second home game in a row, Pochettino turned to Eriksen to try and unlock the door, but even the Dane could not make a difference.
In the end, they were looking for another intervention from VAR after Kane was felled, but it upheld Mike Dean's decision in a moment that will surely bring more focus on the system.
As it was, Spurs should have taken a point, but Moura blazed Moussa Sissoko's cross over as they suffered a second Premier League defeat at their new home.