STILL feeling the effects of a bruising showdown with Joel Selwood, Melbourne tagger James Harmes is relishing the prospect of taking on the AFL's most prolific ball-winner.

Harmes is a near-certainty to be tasked with shutting down Hawthorn star Tom Mitchell when the Demons and Hawks face off in Friday night's semi-final at the MCG.

The 22-year-old's reinvention as an old-school tagger in the second half of the season has been a major trump card for Melbourne with GWS gun Josh Kelly, West Coast's Luke Shuey and Geelong skipper Selwood among his scalps.

No assignment is likely to prove more difficult however than stopping Mitchell, whose AFL-record 54 disposals against Collingwood in round one set the tone for a remarkable season.

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Voted by his peers as the league's most valuable player, the rarely-beaten Hawk looms as a key to keeping his side's finals campaign alive.

But Harmes, who prides himself on his ability to make an impact offensively while playing shutdown roles, reckons he'll go for a minimalist preparation.

"I'll watch a few clips but nothing too serious," he told AAP.

"You know how he's going to play - he's inside so you can't really (over-prepare). You're just going to be watching the same things.

"He's strong in the contests and really clean. If I do get the job on him I'll keep it simple, back myself one-on-one and go from there."

Harmes' ability to get under the skin of his opponents was epitomised during the Demons' elimination final win when he goaded Selwood into giving away a free kick as Geelong forward Tom Hawkins prepared to line up for goal.

Hawkins was denied the chance to cut the margin to 15 points late in the third quarter and the Demons had all the momentum from there.