Rivera said Benjamin underwent an MRI exam and "came back pretty good" after some feared the Panthers' leading received sustained another major knee injury in Sunday's loss to the New Orleans Saints.
"There was nothing structurally wrong, which is good news because that was his repaired knee," Rivera said.
Benjamin's status for Week 4 at New England will be uncertain until closer to gameday.
Benjamin tore the ACL in his left knee in 2015. He has nine catches for 110 yards in three games this season.
Carolina is struggling to find a rhythm offensively with tight end Greg Olsen (foot) and center Ryan Kalil (neck) sidelined and quarterback Cam Newton fighting through what he described as minor injuries.
Olsen is out until late November. Kalil is improving, per Rivera, but not timeline for his return has been discussed.