Paul was sent for an x-ray following the 18-14 defeat at The Willows and looks likely to miss the trip to Edinburgh.
Head Coach Shaun McRae said: “Robbie fortunately hasn’t broken anything, but he did suffer a trauma to his shoulder and neck area and would have to be rated as extremely doubtful to play against Harlequins at this stage.”
Fellow Kiwi Smith could also miss out, after he too limped out of Saturday’s match, with a knee inury.
“Jeremy’s knee is improving and the signs are good, but we are still waiting to see the full extent of the damage. He caught his knee awkwardly in a tackle and again I’d say you’d have to rate him as doubtful to play.
“Craig Stapleton also had a minor foot problem but he will be fine and will definitely play at Murrayfield and we will have Ian Sibbit and Mark Henry available while Steve Nash came through the reserves victory well.”