Thompson was carried from Cazalys Stadium on a stretcher after a heavy collision with Richmond midfielder Matthew Arnot in the third quarter of the Suns' nine-point loss in Cairns.
"I think it's his shoulder or his chest, so we'll just wait on the scans," coach Guy McKenna said.
"He's gone to hospital and he walked to the car. I think that's a good thing.
"He's had a super season. At his age and with his experience as a backman, he's stood up under some fierce weight of numbers.
"With Travis Cloke next week, we'd be pretty keen on a very positive result from the scans, that’s for sure."
Thompson held opponent Jack Riewoldt goalless and to two marks before injury struck, with Seb Tape then moving on to star goalkicker and impressing in his first game back from a serious knee injury.
McKenna will now ponder a recall for key defender Nathan Bock after the 30-year-old, who is returning from a broken leg, kicked nine goals in the Suns' reserves side on Saturday.
"That's his second game ... we've just got to weigh up whether he's going to be OK to run at AFL standard," the coach said.
"There are some boys that are running around thinking they're at AFL intensity, but they might be just a bit off. That's what happens when you start to lose personnel.
"We've just got to make sure we pick a very fit running side next week."
After a bright start kicking with a strong breeze, McKenna said his players had dropped their intensity in the second quarter and allowed Richmond to score easily from the midfield.
With the club's three-year deal to play Richmond in Cairns now over, the coach was hopeful another club would sign on to play the Suns in northern Queensland from next year.
"It's a terrific venue and we're used to the conditions, which you'd like to think is a bonus for us," he said.
"The ground's great, the lights are good, we're 2-1 up here. I can't boast that on too many grounds.
"We'd certainly look at that opportunity if it arose, that's for sure."
Nathan Schmook is a reporter for AFL Media. Follow him on Twitter @AFL_Nathan
