Pochettino started five players who featured in the semi-finals in Russia last month and who resumed training less than a week ago.
The gamble paid off as first-half headers from two of those -- Belgian defender Jan Vertonghen and England midfielder Dele Alli -- secured the points at St James' Park on Saturday.
Tottenham boss Pochettino insisted he had no hesitation in throwing his big-name players back into the fray at such short notice.
"To be fair, all the players came back in good condition and we had some outstanding performances from those who've been away at the World Cup," he said.
"They showed their professionalism and commitment to the club."
Harry Kane was among those returning to action after a significantly truncated pre-season, and the England captain understandably lacked sharpness following his Golden-Boot-winning exploits.
The forward drew a blank on his return to see his wait for a Premier League goal in August stretch to almost 1,000 minutes, a barren run spanning 14 games.
"I think he's in good form, but of course, he can't score three goals every time he goes out to play," insisted Pochettino.
He added: "It was always going to be difficult coming to a place like this on the opening day of the season to play such difficult opponents, so this result makes me extremely proud of the players.
"Many only came back and started working on Monday, so they deserve massive credit.
"We can do better, of course, and be more consistent but it was a massive challenge to connect everything and prepare in the few days we had.
"I am not going to complain and we have to learn to be clever."
Newcastle levelled through their Spanish striker Joselu, but were let down by poor defending for both Tottenham goals as the visitors claimed opening-day success at St James' Park for the second season running.
"We deserved at least a point," insisted manager Rafa Benitez, whose side struck the frame of the goal twice in the second half through Mohamed Diame and substitute Salomon Rondon.
Benitez added: "You could see our team spirit and work-rate, and with the chances we created, we deserved something from the game.
"However, if you make mistakes against good players it's difficult to stop them with their quality, pace and strength."
Newcastle made a £20 million profit on their summer transfer business, despite bringing in seven players, fuelling protests from fans.
Benitez knows he has to work with what he has got for at least the next five months as he looks to build on last season's impressive 10th-place finish.
"The window is closed so it's clear that we can't change anything now," he said.
"The reaction to this result is to work harder. I'm stood here praising my team for doing well, but still we have lost."