Bellerin, 22, spent eight years at Barcelona’s La Masia academy before joining Arsenal in 2011.
In recent years the right-back has been linked with a return to his boyhood club, but Bellerin hailed the high levels of professionalism at Arsenal in his address to the Oxford Union.
Barcelona’s academy La Masia is widely regarded as one of the finest in world football and has seen the likes of Lionel Messi, Xavi, Andres Iniesta, Cesc Fabregas and Gerard Pique come through their ranks.
But Bellerin suggested that the successful emergence of some of the world’s top talent had nothing to do with the training structure and insisted that Arsenal’s methods were far more professional and impressive.
“It was like night and day, the difference between Barcelona and Arsenal,” he said.
“At Barcelona I was just 8-16, when I came to Arsenal I was a professional footballer.
“At Barcelona we were just kicking around on the pitch, at Arsenal, my first day, there were no balls.”