The move almost came about in 2003 with the 18-year-old Ronaldo set to leave Sporting CP. Lionel Messi was still a year away from his senior Barca debut - but if things had worked out differently, he could have been coming into a team with Cristiano as a teammate.
Lapota has explained how that summer an agent offered Barcelona a deal for Ronaldo. But the club were about to sign Brazilian magician Ronaldinho from Paris Saint-Germain, so declined the deal.
"We were about to sign Ronaldinho and Rafa Marquez," Laporta said in an interview reported in Marca. "Marquez's people proposed Cristiano Ronaldo to us. He was at Sporting Clube at the time."
"One of his agents said that they had a player who they had sold to [Manchester] United for €19 million, but they'd sell him to us for €17 million.
"But we had already invested in Ronaldinho at the time. Cristiano played more out wide than in the centre.
"We thought we were covered, so we rejected him and I don't regret it."
Instead, the deal for Ronaldo to Man United went ahead - making him the most expensive teenager in the world at the time - while Ronaldinho began a trophy-laden five-year spell at Barcelona.
So it's hard to say either club did badly out of that summer, especially as Ronaldinho did such a fine job in mentoring and nurturing the talents of the teenage Messi.
But it's amazing to think how different football history would have been if Barca had said yes to that agent's proposal.
Ronaldinho, Messi and Cristiano Ronaldo playing in attack at the Camp Nou sounds like a mouth-watering prospect (unless you are a Real Madrid fan).
Instead, Ronaldinho led Barca to Champions League glory in 2006, winning the Ballon d'Or. Ronaldo did exactly the same for Manchester United in 2008. Then in 2009, he signed for Real for a then world-record fee of £80 million.
Laporta may claim he doesn't regret turning down the chance to sign Ronaldo - and Ronaldinho, alongside Mexican defender Rafa Marquez, certainly helped transform Barca's fortunes. But Cristiano Ronaldo for €17 million sounds like pretty good business to us.
All imagery: PA Images
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