Jones, whose side face Wales in Llanelli, says if Pivac "is given time he'll do a great job".
"It's been a tough time," Jones added.
England's head coach also told BBC Sport: "The media and fans are going at him. People tend to look the other way when they see you.
"You see board members in the corner talking. You go and get petrol, the guy at the petrol station tells you who you should pick.
"He'll be feeling the pressure now but he's a good, young coach and if he's given time he'll do a great job for them.