Joshua reclaimed the WBA, IBF and WBO heavyweight titles after securing a convincing unanimous points decision over Ruiz, who came into the might more than a stone heavier than their first contest on 1 June this year.
In doing so, Joshua became a two-time world champion, having taken a far more concentrated approach on his preparations for a fight that had the potential to make or break his career.
But Ruiz was very much the opposite, with the Mexican-American choosing to embrace his world champion status between the two fights by eating and drinking without restraint, resulting in a large weight-increase and below-par performance on Saturday night.
“I would have loved to have trained the way Andy trained!” joked Joshua, appearing on ITV’s Good Morning Britain from Saudi Arabia on Monday morning.
“I would’ve loved that but that’s not the way of a champion. Andy can say all these things but he knew he had a fight and he knew the best way to prepare. Unfortunately it didn’t go his way and I’m sure he can make those changes, and learning life’s lessons come in different forms and Andy’s was in the form of a loss as well [as mine].
“He knows his mistakes, whatever they were or maybe they’re excuses, he just needs to go out there and get it right and come back again.”
Joshua also expanded on why part of his approach was to block out the voices who told him that facing Ruiz in an immediate rematch just six months after being stopped by him was a mistake.
The Briton was knocked down four times in June on his way to the first defeat of his professional career, a result that was even more of a shock given that he sent Ruiz to the canvas first in the third round.
“No excuses for the last time, and I don’t want anybody to write Andy off,” Joshua added. “He’s a great former champion and he done well and he beat me fair and square. Sometimes you just have to recheck yourself and that comes in many different forms and mine was in a loss, and this time I was really concentrated on my job.
“I just didn’t listen to these so-called boxing experts who claimed that I wouldn’t be able to reclaim my belts and it’s dangerous going straight into a rematch – not many heavyweights have been able to reclaim their belts – but I believed in my team, I kept my same team that everyone told me to get rid of and I feel like loyalty proves strength and we went out there and proved how good we really are now.
“Two-time heavyweight champion of the world, I’m thankful, I’m grateful to be on the TV and all the great things that are going to start happening for me.”
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