The Espanyol side comprised players with La Liga experience including former Hercules pair Pere Martinez Sastre and Borja Martinez.
But the visitors gave as good as they got in an energetic first half and when Roy Krishna broke through on goal after 20 minutes, Espanyol keeper Koke was forced into a good save.
Two minutes later Espanyol saw a deep free-kick pop harmlessly off the top of the Auckland City crossbar.
The home side then missed another good chance when defender Raillo miscued a free header from the penalty spot following another good cross by Peres Martinez.
The New Zealand side spurned a half-chance of its own just before halftime when the hardworking Tade was foiled by goalkeeper Koke.
Tribulietx was pleased with the performance given several mitigating factors.
"We could've come away with at least one goal and we moved the ball really well and we had more possession than Espanyol in patches.
"The first half we were more solid, but bear in mind some players played a full game and jet lag was maybe a big factor with some wayward first touches and physically a bit tired which is understandable," he said.
He also believes there were plenty of positives to build on.
"We need to make sure when we have the ball we don't force it and defensively we were very well structured and they didn't really break us down so the answers here are clear," he said.
Both teams made wholesale changes for the second half and the momentum swung back toward Espanyol.
The Spanish outfit missed an excellent chance to take the lead just after the restart when Auckland City lost possession on the edge of the penalty area only for Arthur to miss the target completely.
But Espanyol pressure finally told when Mamapou picked up a loose ball in midfield before hitting an unstoppable long range strike beyond substitute goalkeeper Louie Caunter on 65 minutes.
Auckland continued to press but lacked an edge in front of goal despite getting good service down the right from both James Pritchett, Ryan de Vries and John Irving.
The young Caunter also pulled off a brilliant save from influential Espanyol midfielder Miravent with 15 minutes left to keep the scoreline tight.
Tribulietx put the final result into context with the FIFA Club World Cup now just seven days away.
"Every team in Spain has more than 30 or 40 players to pick from and we don't. But we had a lot of young guys on in the second half and it was a great opportunity for them to play a side like this.
"Espanyol were faster, have a great touch and when you get the ball a side like Espanyol squeeze you very quickly.
"Its great for their development and I think these young players are going to take a lot of positives out from this experience," he said.
Auckland City move on from Barcelona to their base in Agadir, Morocco, tomorrow afternoon. The match with Raja Casablanca - whose coach was fired last week - takes place in Agadir on December 11.
