JEREMY McGovern is the AFL's Plasticine Man, and he looms as a key figure in shaping West Coast's flag fortunes.

McGovern has established himself as a star of the competition this year, with his expert reading of the play and strong contested marking a feature of his game.

But the 23-year-old has also become known for his knack of being wounded by a host of knocks, niggles and ailments.

The sight of McGovern limping towards the bench has become a common occurrence.

One moment he's in a world of pain and seemingly done for the day. The next, he's pulling off a gutsy contested mark after being assured by the club's medical staff that everything is OK.

The situation has become a running joke among Eagles players, who love McGovern's bravery but can't help but laugh about his vulnerable body.

Former Eagles coach Ken Judge even quipped that McGovern must be made of plasticine.

"Over summer, he needs to get a bit of muscle on those bones," Eagles defender Sharrod Wellingham said with a laugh.

McGovern's hot form was rewarded by being named in this year's preliminary 40-man Virgin Australia All Australian squad despite missing four games with a hamstring injury.

His ability to hold down a key defensive post in the absence of Eric Mackenzie and Mitch Brown has played a vital role in West Coast's surge into premiership favouritism.

Knocks to his knee and calf have been other things to affect McGovern this year, but it's an ongoing shoulder injury that is threatening to hamper his output during the finals.

McGovern injured the AC joint in his left shoulder when Adelaide spearhead Taylor Walker crashed over the top of him in round 22.

In the qualifying final win over Hawthorn, McGovern struggled to even lift his left arm at times, forcing him to use his right arm to spoil when he would otherwise be going for the mark.

Backman Will Schofield would rather a one-armed McGovern than no McGovern at all - and the rest of his teammates agree.

"His shoulder is going to be sore. But he's a really important cog in our machine," Wellingham said.

"Him being out there is really crucial."

McGovern could get the job on Drew Petrie, Jarrad Waite or Ben Brown in Saturday night's preliminary final against North Melbourne in Perth.

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A podgy McGovern was infamously banished to the WAFL in 2013 after rocking up to pre-season training unfit.

Although his body type means he will probably never be as lean as his teammates, McGovern has worked hard to lift his fitness up to the standards required to thrive in the AFL.

"He's fearless with how he goes about it," Eagles veteran Sam Butler said.

"You grow in confidence as a group when you've got someone like that around you.

"He's been a standout in our backline this year.

"He does take some hits because he wants to jump at the ball in those packs.

"He's a strong lad."