The Blues confirmed on Monday that Cerra had suffered a low-grade strain after he was subbed out in the third term of last Friday night's upset win over top side Collingwood.
They say it will put him out of action for two to three weeks.
Walsh missed the Collingwood game - Carlton's sixth win a row - because of his injury, while Cerra returned from hamstring tightness to play the Magpies.
Cerra's setback comes as Blues livewire Jack Martin declares he is "absolutely confident" he has overcome his injury woes and will be able to play a key role as Carlton seek an end to their decade-long AFL finals drought.
Martin missed three months because of calf trouble during the first half of the season and was substituted out of his first two games on return.
He also sat out the thrashing of West Coast in round 19 but returned with a bang in last week's upset of ladder leaders Collingwood, booting three goals.
It would have been four - an equal career-best tally - if a gettable late shot on the run had not drifted wide.
Clearly relieved to be back on the park, Martin said he had "been everywhere, seen everyone" in his bid to overcome his calf issues.
"I missed a chunk of footy in the front half of the season but I've been able to get myself right and the body's feeling good," Martin told AAP.
"I'm just happy to be back out there playing footy with the boys.
"I've seen a few different specialists and I've tweaked a few things in my program, and a lot of strength work is certainly helping.
"I'm trying to turn every stone over to get my body right."
The winning streak has thrust Carlton back in the top eight after all hope looked lost at the halfway point of the season.
The Blues can strengthen their grip on a finals spot with victory over fellow top-eight side St Kilda on Sunday before meetings with Melbourne, Gold Coast and GWS in the run towards September.
"(Beating Collingwood) gives us a lot of confidence," Martin said.
"It was more about us and what we wanted to bring because we knew that our game would stand up against anyone.
"Collingwood's been a great side all year and there was no better way to test ourselves.
"It was an unbelievable win by the boys. We really focused on contest and pressure and everything happened on the back of that."
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