But Jones insists Jenkins will not be cowed by the reaction to Wales' thumping 62-5 defeat and will bounce back with pride to oversee a successful World Cup campaign.
"I wouldn't say it is water off a duck's back because Gareth is a proud man and doesn't like to be criticised," said Jones, who played under Jenkins at Llanelli.
"He is very passionate. He will know that team didn't play their best at the weekend and Gareth will be unrelenting in his work ethic to ensure that never happens again.
"Gareth is a proud guy. You don't coach at Gareth's level for as long as he has if you don't have passion and fire in your belly."
Jenkins reacted defiantly on Tuesday, accepting Wales were in a no-win situation at Twickenham but urging the public and the media to judge him on the World Cup.
Jones said: "He has come under criticism before and he has bounced back. He will do the same now and so will the players.
"We can't afford to be negative now, we have to stick together. I am convinced that in six weeks time it will be completely different and that there will be a good World Cup in progress."
Jones, certain of a place in Wales' 30-man World Cup squad, was not involved at the weekend as Jenkins looked for fringe players to force their way into his thinking ahead of Friday's announcement.
He admits the Twickenham hangover could be difficult to shift for those players who make it onto the plane to Nantes, where Wales open their World Cup campaign against Canada on September 9.
"It was hard to watch. I was probably not as disappointed as those who played because there is nothing worse than coming off after you have lost badly," said Jones.
"What can you say to the boys who came off the field? They didn't go out there with the intention of losing by that score.
"The fact it is the old enemy makes it more of a bitter pill to swallow."