Rivera said depth on the offensive line is his biggest concern personnel-wise, and that the Panthers will look to sign another player to help out.
Carolina is 1-3 heading into Sunday's game at Minnesota.
"It's kind of been two seasons in a row where we've kind of had to go through this," Rivera said of injuries to the line. "Last year we played well down the stretch with a group of young guys that hadn't gotten an awful lot of snaps prior to this.
"I believe it's something we can work on and get going in the right direction."
That the Panthers allowed seven sacks against Arizona adds to Rivera's concern. He blamed some on miscommunication, some on quarterback Cam Newton holding the ball too long and some on Arizona doing things scheme-wise to confuse the offense.