In a sensational bit of business, Manchester United re-signed Ronaldo from Juventus towards the end of last month, 12 years after he originally left the club in 2009.
The 36-year-old has trained with Manchester United this week and is widely expected to make his second debut in the starting eleven against Newcastle United on Saturday afternoon.
But Thompson feels there is a chance that Ronaldo could be on the bench to start with against the Magpies.
He stressed that the atmosphere will be electric inside Old Trafford if Manchester United need a goal in the last quarter of the game and Ronaldo comes on from the bench to make his second debut for the club.
Thompson said on the Where’s Jeff podcast: “Man United have had a decent start so who does he come in for?
“There is something in the back of my mind that he is going, ‘put him on the bench’.
“He will come on at some point anyway, but just say it is not going right, you can imagine him coming on with 25 minutes to go and that place will be absolutely bouncing.
“I can just visualiase him taking that tracksuit off and just getting ready.
“Something is telling me that he is going to be a sub.”
Ronaldo is tipped by many to start on Saturday against Newcastle, who were the opposition against the Portuguese scored his only hat-trick as a Manchester United player in his previous stint.