The veteran Swan spent a lot of Saturday night's 65-point win over the Brisbane Lions in reasonably unfamiliar territory - the forward line - but adapted quickly, kicking three goals opposed to in-form Lions defender Daniel Merrett.
Robert-Thomson's third goal brought his career tally to 19, from 137 games.
Roberts-Thomson also spent time in the ruck, with three hit-outs.
"I am just happy to play where the coach wants me to play, wherever the best fit for the team is, and tonight it was up forward," Roberts-Thomson said after the match.
"I was on Merrett and he is a fantastic player and he is very good at reading the play and my role was to take him deep so he wouldn't have as much influence as he has and by doing that, hopefully I generated some play for us.
"Having that defensive background, it allows me to make a contest."
Coach John Longmire said Roberts-Thomson's three goals, a career-best (beating his previous of two goal against Geelong in 2003), were a bonus to the defender's initial role of keeping tabs on Merrett.
"He has played there the past couple of weeks, because we are obviously missing Shane Mumford and Kieren Jack, and he kept Merrett out of the game to a large degree," Longmire said.
"He wasn't tagging him, he was just making sure he kept the defence honest.
"I thought he looked pretty agile at ground level, which I know he is."
However, Roberts-Thomson laughed off a permanent shift to the forward line.
"I don't know about that, I am just trying to keep it simple," he said.
"Hopefully tonight's performance shows that we are a team that is really improving.
"We want to play for one another and tonight we took a few steps in the right direction."
