In the blink of an eye on Friday afternoon, Rory Thompson went from planning to stop exciting GWS forwards Jeremy Cameron and Jonathon Patton, to being Gold Coast's number one ruckman.

Thompson, who had a breakthrough year at fullback in 2013, was studying footage of Cameron and Patton when his match preparation was thrown a late curveball.

First-choice ruckman Tom Nicholls (calf) pulled up sore from the team's final training session and was ruled out.

With Zac Smith in the late stages of overcoming a full knee reconstruction, and Charlie Dixon (groin) making his return through the reserves on Saturday, the SUNS' cupboard for ruckmen was bare.

Thompson played there as a junior, but admitted it was "years" since he had taken on any more than a pinch-hit role in the position.

"I just finished doing my edits on Patton and Cameron and then big (midfield coach) Matty Primus walked in, put his head down and I got told the good news," Thompson laughed.

"I chopped out a bit last week and I just had to play my role, compete, and that's it. I wasn't overly stressed."

The 200cm Thompson was clearly beaten in the hitouts by Jonathan Giles (51-27), but competed well enough to allow the brilliant SUNS midfield to dominate the clearances (44-36).

SUNS coach Guy McKenna admitted post-match he had asked a lot of the 23-year-old, particularly after a pre-season limited by a hip arthroscopy.

"To throw him into the ruck and run like he did all day was a terrific effort," McKenna said.

But neither McKenna or Thompson want it to become a regular option.

Nicholls is expected to be available next week, as is Dixon who was promising in his return at NEAFL level.

"As the day went on, I started remembering back to the old junior days of playing ruck and what to do," Thompson said.

"Hopefully we'll get our talls back on the track and I can settle myself back in defence for the rest of the season.

"I'll be on their backs making sure they do all their recovery this week," he joked.