They hung on well for the first 25 minutes - though under pressure - before the levee broke, with a goal, via a slightly fortunate deflection, from Brazilian striker Romarinho.
Two more in 12 minutes - including one to French superstar Karim Benzema - ended the game as a contest, though the Oceania champions showed good spirit to compete well in the second half.
But the Saudi all stars were always going to be too strong, recording 30 shots to four across the match.
Benzema had scored more than 350 goals for Real Madrid, won the Uefa Champions League five times and was judged the best player on the globe in 2022.
Al-Ittihad also had N’Golo Kante, a Fifa World Cup winner with France who was rated as one of the best players in the English Premier League during his long spell with Chelsea. They had Fabinho, the Brazilian international lured away from Liverpool for $82 million.
And there were numerous others.
Al-Ittihad had so signed so many players there are some they can’t even use in the domestic league, which has a limit of eight foreign players - like Portuguese winger Jota, who was bought from Celtic for $50m. Since June they have been backed by the Saudi government’s Public Investment fund, the same group behind LIV Golf and Newcastle United. Al-Ittihad have spent colossal amounts since in transfers and wages, with Benzema’s reported annual salary comparable to New Zealand Rugby’s total revenue in one year.
It was a ridiculous scenario but Auckland City could only try to compete, in their 11th Club World Cup appearance.
They did that well for a period, weathering the storm and enjoying a couple of promising moments in the final third. Al-Ittihad had chances - but couldn’t take them - and the New Zealand side were well organised defensively.
Just as the 50, 248 crowd in Jeddah were starting to get restless, Al-Ittihad made the breakthrough, with Romarinho slamming home from the edge of the area. It was hit well - though a deflection was key to the shot eluding goalkeeper Conor Tracey.
Tracey made a superb stop from the same player moments later, before Kante - who won the Premier League with both Leicester City and Chelsea - produced a thunderbolt, after the ball fell to him from a corner.
From there Al-Ittihad could relax, while Auckland City were deflated, as the physical and mental exertions started to take a toll. Benzema added a third - after some clever build-up play - becoming the first man to score in four different editions of this tournament.
Auckland City pushed more in the second half, forcing a string of corners and enjoying more possession, as the Saudi team were prepared to sit on their lead. Coach Albert Riera rolled the substitutes, with veteran Emiliano Tade coming on for a record 12th Club World Cup game.
Striker Liam Gillion had the best chance but his first touch let him down in the area, closed down as he prepared to shoot.
Auckland City 0
Al-Ittihad 3 (Romarinho 29′, N’Golo Kante 34′, Karim Benzema 40′)
Halftime 3-0
Michael Burgess has been a sports journalist since 2005, winning several national awards and covering Olympics, Fifa World Cups and America’s Cup campaigns. A football aficionado, Burgess will never forget the noise that greeted Rory Fallon’s goal against Bahrain in Wellington in 2009.