UFC analyst Joe Rogan has revealed that Anthony Joshua was knocked down and hurt in sparring the week of his shocking loss to Mexican underdog Andy Ruiz Jr.

The boxing world experienced a huge shake-up on Saturday night, as unheralded heavyweight Andy Ruiz Jr (33-1, 22KOs) stepped in on short notice and produced a stunning seventh round TKO over England’s Anthony Joshua (22-1, 21KOs) in front of a packed crowd at Madison Square Garden in New York.

The fight was billed as Joshua’s US debut and a chance for American audiences to witness his greatness in prime time, but the night belonged to Ruiz, an 11-1 underdog who’d never picked up a top-10 win prior to Saturday, and has since become the WBO, WBA and IBF heavyweight champion of the world.

Among those who have their opinion on Joshua’s lacklustre performance, which saw the previously undefeated Brit drop to the canvas on four separate occasions, is UFC analyst Joe Rogan, who chimed in on his theory as to why AJ simply wasn’t himself in the ring.

“I have it from a good source, that Anthony Joshua got dropped in sparring the week of the fight,” said Rogan on the JRE MMA Show with Kevin Lee.

“He got hurt real bad the week of the fight and he was very tentative and vulnerable coming into the fight…which makes sense.”

Ruiz is the first heavyweight champion of Mexican descent and has lined himself up for massive paydays down the line, including the now confirmed rematch with Joshua which will be in November or December later his year.

This was a fairy tale story come to life, an underdog who shocked the world and now holds three out of four of the sport’s major belts within the division.

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As for Joshua, the Watford-born slugger must go away and reflect on what was a bitterly disappointing night for the former champion.

After taking a vicious shot to the head from Ruiz in the third round, his legs began to shake and he lost all mobility in the ring, basically becoming a human punching bag for his Mexican opponent.

Adjustments must be made ahead of the eagerly anticipated rematch later in the year, where AJ will look to reclaim his throne atop one of the most competitive divisions the sport has ever seen.