Cape Town - They were riding on the crest of a wave with an unbeaten record in 19 games in all competitions, seemingly running away with the Absa Premiership title and, to all intents and purposes, living up to the club's motto of "the sky is the limit."
But it was a rude reminder for billionaire Patrice Motsepe's Mamelodi Sundowns club when they suffered a deflating 1-0 defeat against relatively unheralded Chicken Inn in the first-leg preliminary round game in Bulawayo last week-end, discovering at the same time that while the sky might well be the limit, you have to learn to keep your feet on the ground first.
And herein lies the devastating indictment that the team nicknamed The Brazilians had their heads in the clouds before taking on the Zimbabwean champions when club officials of the Chloorkop club began to compare their attacking trio of Keagan Dolly, Khama Billiat and Colombian Leonardo Castro with the currently incomparable Barcelona frontline of Lionel Messi, Luis Suarez and Neymar.
It was, of course, quite ludicrous and seemingly based on one exceptional goal against Orlando Pirates in which Dolly, Billiat and Castro were seemingly telepathically involved.
Messi, Suarez and Neymar have combined to score dozens of such goals and are widely considered to be among the four most accomplished players in world football along with Real Madrid's Ronaldo.
So, for sure, Sundowns were more than a little carried away by their ongoing success and paid the penalty while tasting what was an unappetising defeat against Chicken Inn.
The good news for The Brazilians is that there will be an opportunity to make amends in the second-leg on more familiar turf next weekend.
But they cannot repeat the mistake of believing that success for them is ordained, particularly against a side that has surprising resilience and discipline in spite of having few of the financial resources available to Sundowns.
And hey, this is only a preliminary round fixtures and emphasises the gruelling road that lies ahead for Sundowns and other South African Champions League participants Kaizer Chiefs in order to win the prized continental title - or even make it to the closing rounds of Africa's most prestigious club event.