The Saudis stunned City in extra-time to win 4-3, with Guardiola later acknowledging the form of Morocco goalkeeper Bono making the difference.
He said afterwards: “At this stage, they are all difficult games.
“We allowed them to create transitions but we created a lot and in general we were good.
“It’s a pity. We were in such a good place and I cannot say thank you enough to the staff, how they train and prepare, they have given everything.
“We made a lot of actions and Bounou made incredible saves. Nothing else to say.
“I have the feeling that the team is doing well but we go home and now time to rest and refresh our mind and come back next season.”
Bono made difference
Guardiola insists he leaves the US pleased with the progress of his team.
He added, “I saw many good things that I didn’t see in the past, especially how we were, the relations between the players and the staff.
“I felt we were happy here and the sessions were really good but the levels here are so high.
“The chances we had, they defended so deep and Bono made a lot of saves but you have to score and be so clinical.”