Walker is expected to return to senior ranks against Collingwood on Thursday night after a year-long absence due to a knee reconstruction.
But his teammate Smith called for tempered expectations on the star spearhead.
"He will give us a big boost up forward and just having him in the side sparks the boys up, but to put all our hopes on Tex is unrealistic," Smith told reporters on Monday.
"He's not going to come in and set the world on fire straight away. It will take a bit of time to get back to his best.
"But he has played really good footy in the SANFL, so who knows, he might come out and play really well. Hopefully he does."
Walker, who has played two games in the SA state league, will return along with midfielder Richard Douglas, who has served a two-match suspension.
Influential midfielder Patrick Dangerfield trained fully on Monday, having removed a protective boot from his injured left foot, and will play against the Magpies.
The Adelaide Oval game is a sell-out and Smith said Walker would relish his return on a big stage.
"We saw the way he performed when we had finals a couple of years ago - he's a big-game player and Thursday night is going to be a big moment for the club ... he'll really thrive on that," Smith said.
"He's always up and about in the change rooms and at training, but I suspect come Thursday he'll be a bit nervous.
"We will try and get him the footy early, slip him a few, try to get him a few lead-up kicks. We will just get the footy in his hands early and hopefully he kicks one and gets going."
The Crows enter the match with three wins and four losses - their last defeat was against lowly Melbourne before their bye last weekend, which was used for reflection.
"I wouldn't say soul searching, but we had four days to go away and really reflect on our own games," Smith said.
