They’re the gamekeepers turned poachers — AFL key defenders being used with growing effect in attack.

Melbourne’s Tom McDonald has played that swing man role this season and kicked 23 goals.

It gives Brisbane coach Chris Fagan something extra to think about ahead of Sunday’s clash at the MCG.

It’s only a small club but Harry Taylor’s best-afield performance last week for Geelong in the win over Richmond showcased their potential.

With Tom Hawkins suspended, Taylor played on All-Australian full-back Alex Rance and not only took him out of the game, but kicked four goals as well.

McDonald took careful note and no doubt colleagues such as Collingwood’s Ben Reid did as well.

“The Rance and Taylor one was very interesting; obviously you have a defender that (Geelong) are trying to take out of the game,” McDonald told AAP.

“That’s a rarity, except for maybe the running half-back flankers.

“Then to be able to kick goals as well, that’s a huge effort on Rance.

“I follow those ones with interest, because it’s tough to actually be able to do that in practice.”

McDonald went back to defence last week for the win over St Kilda after several weeks in attack.

Key forward Jesse Hogan is back from a broken collarbone and that, combined with Melbourne’s good mix of goalkickers against the Saints, probably means McDonald will start down back.

“Every week, we’ll make the call on what’s best depending on injuries, form and what’s needed,” McDonald said.

“Even the opposition — whether they have two or three tall key forwards or maybe they have a lone key forward … maybe then they don’t need me to play back.”

The Demons will start strong favourites against the young Lions, who are last, but McDonald said they are well aware not to take them for granted.

Brisbane have impressed under coach Chris Fagan and if Essendon miss the finals, they will rue their round-15 loss to the Lions.

Likewise, Melbourne’s campaign for their first finals series since 2006 suffered a hiccup with the round 19 loss to North Melbourne.

But unlike Essendon, Melbourne are in the top eight, so they control their destiny with games against Brisbane and Collingwood to come.

“It’s not daring to dream, it’s almost the opposite — getting to work and putting the hard hat on, rather than dreaming about it,” McDonald said.

“We’ve had a couple of good weeks’ ‘prep’, we’ve been in Melbourne for a few weeks now and we’ve been able to get in some more training, which has been really important.”