Whyte was knocked out cold by Povetkin in the main-event of Matchroom's final 'Fight Camp' show on Saturday.
The Brit floored the Russian twice in the fourth round before succumbing to a vicious uppercut that floored him in the fifth round.
And heavyweight rival Ruiz Jr pulled no punches as he aimed a dig at Whyte after he lost his WBC mandatory status.
"I was so happy that Whyte got his a*** knocked the f**k out," the Mexican-American said.
"You know what, because he doesn't have respect for the fighters - that's what gets me p***ed off."
The former unified world heavyweight champion also poked fun at Whyte on Twitter.
- AndyRuizjr (@Andy_destroyer1) August 22, 2020
Ruiz Jr hasn't fought since surrendering his world titles to Anthony Joshua last year.
Whyte, meanwhile, is set to rematch Povetkin after promoter Eddie Hearn revealed that they have a rematch clause in place.
Wow..truly gutted for Dillian. Big respect to Povetkin for pulling that out of the bag.I believe Dillian will bounce back in the rematch! Bitter sweet but #FightCamp has been the best thing I have ever been involved. Thanks for the support,this really is the greatest sport of all
- Eddie Hearn (@EddieHearn) August 22, 2020
Speaking after his show, he said: "We have a rematch clause. First thing Dillian said when he came out was, 'Get me that rematch, get me that rematch.'
"We will exercise that rematch clause, we will look to make that before the end of the year.
"And listen, it's a huge fight. it's a very dangerous fight now because obviously back-to-back defeats for Dillian Whyte throws a very different shade on it.
"But I know that he'll come back from this."
Featured Image Credit: Andy Ruiz Jr/DAZN
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