The Lions beat Western Australia 116-10 at the WACA cricket ground in 2001 but are unlikely to rack up a similar tally on Wednesday against a Super Rugby team who beat the All Blacks-laden Canterbury Crusaders in April.
Sheehan also indicated that Lions fly-half Owen Farrell's spat with Barbarians hooker Schalk Brits in Saturday's tour opener in Hong Kong had flagged up a weakness that the Force might be able to exploit.
"We want it to be an extremely physical game," Sheehan told reporters in Perth on Monday.
"If it gets fiery, well that's good for us. They are stressing that they want to stay disciplined, there were a few little things that got under their skins.
"Maybe we can do the same and we'll see what happens."
The Lions, who arrived in Perth on Monday, were delighted to emerge from their crushing 59-8 victory over the Barbarians in sweltering humidity in Hong Kong with no serious injuries.
"It is such a collision sport that you are going to pick up injuries and we have been lucky at the moment that we have been relatively injury free," coach Warren Gatland told a news conference after announcing his team for Wednesday's match.
The New Zealander knows that luck is unlikely to last forever and Force skipper Matt Hodgson made it clear his team would be out to soften up the tourists both mentally and physically at Subiaco Oval.
"I think any loss is going to be a blow to them," the former Wallabies back rower said.
"They've probably come out and pencilled in victories in most of the games before the test matches.
"So hopefully, if we can't get the win, we can put in a solid performance and hurt a few of their bodies."
Sheehan made his first Test start last year against Italy as Australia coach Robbie Deans struggled with an injury crisis that saw him use 41 players over the season.
The Wallabies have suffered more injuries in recent months and the squad trained in Sydney on Monday without flanker David Pocock, winger Digby Ioane, hooker Tatafu Polota-Nau, back rower Scott Higginbotham and lock Sitaleki Timani.
All of them would have been likely starters in the three-test series and, although Ioane and Higginbotham could still play a part, there is no doubt such absences will have an impact of the team.
"There are some real quality players that Australia have lost or picked up injuries in the last few weeks, which is going to weaken them," Gatland added.
"But from last year if you look at the depth that they have created, and they have also got players who have come back that haven't been available for the last 12 months so, whatever Australian side is going to be put out it will be pretty tough.
"I have been impressed with how their Super Rugby sides have been doing and it looks like a lot of players have been hungry and keen and put their hand up for selection in that Wallaby side."
One such player is Western Force back row forward Ben McCalman, who will miss Wednesday's match in Perth after being called up to train with the Australia squad when Higginbotham dislocated his shoulder at the weekend.
At 1.92m and 106 kgs, McCalman is no weakling but he said he had been impressed by the power of the Lions in Hong Kong.
"It was pretty tough conditions over there but they still managed to be physical for the entire game," he told reporters in Sydney.
"They're very tough, a very big side and that physicality is something we're going to have to match or better."