Lionel Messi or Cristiano Ronaldo? Whatever one's thoughts of the legitimacy of the comparison, there is no denying that it is a question which has defined a generation. Everyone picks one or the other. Well, almost everyone.
In Deco, one could not hope for a more impartial judge, and when the former Portugal and Barcelona midfielder was asked for his preference in the summer of 2016, he found fault with the question.
"Ronaldinho was far more gifted than Leo or Cristiano," he countered. "He was a natural with special ability. Whenever we gave the ball to him, the moves and goals were from a different world."
It is difficult to disagree. After Ronaldo (the Brazilian version) had changed the entire perception of what a No.9 could do, Ronaldinho came along and changed the entire perception of what a footballer could do.
He brought the tricks and flicks of futsal to a full-sized football field. He pulled off pieces of skill that nobody had seen before.
Kevin-Prince Boateng tells remarkable tales of Ronaldinho hitting the crossbar three times in a row in training just because he could. "We wondered how it was possible there was so much talent in one body," he gushed.
Eidur Gudjohnsen, meanwhile, became convinced that Ronaldinho was capable of defying the laws of physics.
"When you play with him and see what he does with a ball, nothing surprises me any more," the former Barca forward admitted. "One of these days, he will make the ball talk."
He could certainly do anything he wanted with it but, as Brazil and Real Madrid legend Roberto Carlos pointed out, "it wasn't just about the tricks - he created and scored the goals to match his ability."
Indeed, his stunning strike against Chelsea at Stamford Bridge in 2004, from a standing position, was the most exhilarating, bewitching and bemusing illustration of him marrying skill and substance.
In truth, there were innumerable examples of his outrageous ability. Indeed, Ronaldinho became a human highlight reel; an entire generation watched Barca games just to see what he could, and would, do next.
Because of a scheduling dispute in the lead-up to an international break, his Blaugrana debut, against Sevilla, kicked off at five past midnight on September 3, 2003.
In spite of that, 80,000 supporters still flocked to Camp Nou to see their new Brazilian superstar. Not one regretted that decision.
At around 1.30am, Ronaldinho picked up the ball inside his own half, skipped past two opponents and then unleashed a stunning 30-year drive that crashed off the crossbar on its way into the net. Barca drew the game but Ronaldinho had brought hope back to Barca. In time, he brought trophies too.
David Beckham once said, "There was a period in Ronaldinho’s time at Barcelona where he was almost unplayable." It was between 2004 and 2006, when Barca won back to back Liga titles, as well as the Champions League.
On a weekly basis, Ronaldinho did things that took that breath away – and all the while with that endearingly toothy grin on his face.
Frank Rijkaard enthused, "He transmits a lot of joy and pleasure playing the game, and he has individual skills that are of such a high level that everybody in the world adores him."