Ruiz not the guy I wanted to be fighting - Joshua

Ruiz's trainer breaks down epic upset of Joshua (5:10)

Andy Ruiz Jr.'s trainer, Manny Robles, dives into each phase of Ruiz's stunning upset of Anthony Joshua to claim the heavyweight title. (5:10)

Former world heavyweight champion Anthony Joshua has said that Andy Ruiz Jr. was not the man that he wanted to face when he lost his three world title belts in a seventh round knockout defeat at Madison Square Garden in June.

Ruiz became the first fighter of Mexican descent to win the heavyweight world title when he knocked out Joshua in the seventh round in New York after putting the British boxer down four times in the fight.

Joshua, 29, has said that he was confident going into the fight, praising his training beforehand, but admitted that Ruiz was not the man he wanted to be facing and had trouble getting his mind right for the bout.

"It's hard, I'm trying to psych myself up, but I don't have any envy or hate for this guy," Joshua said in an explanation video on his YouTube channel. "We haven't even done a press conference, so I didn't feel too hyped up.

"It's hard when nobody's worrying about this guy. They're thinking about the next guy down the line, but I'm looking at this guy. He's a good fighter, that's why we picked him. We didn't pick him because he's an easy walk in the park."

Joshua was originally booked to fight American Jarrell Miller before the Brooklyn-born fighter failed a drug test, having tested positive for a metabolic modulator drug.

"Nothing felt different, I was focused. It doesn't matter where you put me. You could put us in the shed and fight us in the garden, no problem. The objective remains the same, doesn't it? Go out there and do your best. But no, nothing felt different."

Joshua -- who was undefeated going into the contest with 21 knockout wins in his 22 previous fights -- said that he felt confident in the beginning of the fight, with Ruiz "barely getting a sweat" on him.

The Watford-born fighter knocked Ruiz down in the third round of the bout, only to be put down twice himself later in the round, as well as twice in the seventh.

"I couldn't really remember where I was at the time, I just knew that I was in for a fight and that I shouldn't be here [on the canvas] so I got back up to my feet and we went again.

"You know, Ruiz did well and hit me with a good shot and I just couldn't recover from it. My legs and everything, it's like it's a weird feeling.

"From there on, I remember going back to the corner. I couldn't remember what I was saying.

"I think it was like the fifth round I thought I was just recovering -- I would have assumed so, because I was landing more shots.

"Boom, got hit again. As I was climbing, it was like the hole was getting deeper. I don't know, it shows that training went well. I was strong, I was fit. Even though my mind wasn't there, my body was strong, I kept on getting up."

The pair are expected to fight again in a rematch, but are yet to set a date or location for the bout.