Heading into the fixture at a rain-soaked Tottenham Hotspur Stadium, Spurs were under pressure to deliver a bounce-back display after the dismal midweek loss at Manchester United.
But it was yet another uninspiring performance from the hosts, who were jeered off at half-time after two self-inflicted errors allowed Newcastle to ease into a 2-0 lead.
There was somewhat of a response from Spurs early into the second period through Harry Kane (29), but an equaliser against Eddie Howe's stubborn Magpies was rarely threatened.
The result means Spurs have suffered back-to-back defeats in the Premier League for the first time since February, but it has also signified a number of growing issues that Conte must try to address.
Haphazard Lloris a concern
Hugo Lloris (35) was the only Spurs player to come away with any sort of credit against United, with his performance very much keeping the 2-0 scoreline at Old Trafford down.
But he could not manage to follow up his display against Newcastle with his decisions hampering his side on this occasion.
The game's biggest flashpoint came when the Magpies opened the scoring through Callum Wilson (30) after a period of Spurs pressure.
Lloris collided with Wilson around 25 yards from goal after rushing out to beat him to a long ball, with the striker then floating his effort into an empty net.
A VAR check for a foul on the Lloris was launched but it was decided no infringement was made, handing the visitors the lead and momentum from out of nothing.
The Spurs captain was also involved in Newcastle’s second when his kick was intercepted by Miguel Almiron (28), who then weaved his way into the penalty area to slot home.
There have been plenty of times over his Spurs career where Lloris has produced heroics to keep his side in matches, but errors have started to creep into his game on a more regular basis over the last couple of seasons.
And as the club captain and first-choice option in goal, his jitters will not necessarily inspire too much confidence throughout the rest of the team.
Wing-backs continue to struggle
Conte's managerial style is infamous for relying heavily on the actions of the wing-backs to generate play - especially from a creative point of view.
The Italian coach has not always had the best profiles to work with at times, but has more often than not managed to get a tune out of them.
At Spurs, though, he has not yet found a pairing that is good enough for a stretch of games.
Conte rotated Matt Doherty and Ivan Perisic after their difficult evenings against United, bringing back Emerson Royal and Ryan Sessegnon for Newcastle.
But it was an alteration that still did not have a positive impact.
The pair struggled in the attacking third for Spurs, with their distribution failing them more often than not.
And Sessegnon, despite being put in an awkward spot by Lloris, was still shrugged off a bit too easily by Almiron before the Paraguayan winger dispatched his goal.
The lack of cutting-edge from Spurs' wing-backs is just one issue that is hindering the side although Conte does seem a little hamstrung by the quality of the options at his disposal.
Kulusevski absence still being felt
No one could envisage Dejan Kulusevski (22) becoming such an important part of the Tottenham set-up, but that is still being seen in his continued absence from the side.
The Swede has missed the last seven games in all competitions since the international break after picking up a hamstring injury with the national team.
Kulusevski has emerged as arguably Spurs' best creative outlet since his arrival from Juventus in January and his unavailability - potentially until after the World Cup - is significantly hurting the club's attacking play.
Spurs are unbeaten in the six Premier League games Kulusevski has started, averaging 2.6 goals per game and 2.3 points a game. Without, they have won three and lost three, averaging just 1.1 goals and 1.5 points.
Conte attempted to fill the void by using Richarlison - who is now also sidelined with injury - on the right wing, but he was not able to apply himself to full effect out of position.
Lucas Moura (30) has since been eased back into action after returning from injury but is of a completely different profile to Kulusevski, while Conte is still not entirely sold on Spanish youngster Bryan Gil (21).
But the conundrum has in turn led Conte to move away from using three attackers by adding an extra man in midfield, deploying Kane and Heung-min Son (30) as a pair up front.
The change was used against United and Newcastle but the duo often went large parts of both games starved of good quality service.
