WHEN Geelong was deciding whether or not to take a punt on Mitch Clark, coach Chris Scott had an ace up his sleeve.

Scott's final two years as a Brisbane Lions player in 2006-07 coincided with Clark's first two seasons on the Lions' list.

Scott liked what he saw then. And quite a lot of what he has seen since - when the big man has been able to get onto the park.

So when Clark - who had been diagnosed with clinical depression during his injury-riddled stint with second club Melbourne - announced his intention to come of retirement in September last year, Scott and the Cats jumped at the opportunity.

In Clark and 200cm former Saint Rhys Stanley, the club was able to trade in two players who could add to their key forward and ruck stocks.

Geelong sees Clark primarily as a marking forward option alongside Tom Hawkins, although Scott said that role was not set in stone.

"I have seen Mitch have a virtual All Australian year as a ruckman in Brisbane, and on the limited exposed form we saw in Melbourne, he showed he could be one of the really good power forwards in the competition as well," Scott told AAP.

"We're open-minded.

"The one thing about Mitch is, assuming he is healthy and available to play, if it doesn't work for him in one position, he's got other options."

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A wide variety of injuries and the other off-field issues have limited Clark to just 97 matches in nine years in the AFL system, prior to his initial decision to retire early in 2014.

But as Scott points out, at 27 he's only one year older than celebrated Cats captain Joel Selwood, who is at the peak of his powers.

"We know we have a bit of a gap in that middle-age bracket," said Scott.

"Mitch might be at the upper end of that but he's still in the middle.

"And knowing him from back at my time in Brisbane absolutely helped in the decision-making process for me.

"We needed to do a lot of work with the medical experts and his doctors to make sure we were comfortable with that.

"But my assessment was easier than some of our other staff members because I'd had the two years with him and I rated him very highly."

Clark will play his first match for the Cats in Sunday's NAB Challenge clash against Gold Coast in Townsville.