"Motlop and Christensen are not replaceable players," said coach Chris Scott of the dynamic duo, who have developed into key members of the Cats' midfield and forward set-ups.
"But we've got some pretty handy players who will come in and do a very serviceable job.
"It might not be quite as good and people might get sick of me saying that it's all about the long term, but with those guys we're just not going to put them at risk to try and steal a few games early in the season."
George Burbury shaped as a likely replacement at half-forward, only to have his jaw shattered last week in the opening NAB Challenge win over Collingwood.
Scott flagged increased opportunities for youngsters Jordan Schroder, George Horlin-Smith and Jackson Thurlow.
Highly-rated Lincoln McCarthy is also back in the mix after missing all of last year with a serious foot injury, having played a single senior game in his debut season of 2012.
"It does present a challenge, getting injuries to really good players," Scott said.
"Christensen and Motlop are clearly in our very best team and probably in the top half of our best team and it's compounded by the fact that they are similar types of players.
"It's like the case of losing a ruckman hurts, but losing two ruckmen kills you.
"But it will open up an opportunity for some others.
"Sometimes you've got to remind yourself that you should be glass half-full about this type of thing."
Geelong plays Adelaide at Simonds Stadium in round one of the home and away season on March 20.
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