Murphy suffered a severe bout of concussion when he hit his head on the ground during the second quarter of the Blues' 103-point loss to Port Adelaide last Friday night.
He was taken to hospital for scans but was cleared of any structural damage.
"He's still a 'test'," defender Michael Jamison said at Visy Park on Wednesday.
Preview: Blues v Bombers
Stung by the way they were humbled by the Power, Jamison and his teammates are desperate to redeem themselves against one of their arch-rivals.
"We think we've still got plenty on the line," Jamison said. "It's funny how the last few games of a year can really set up your pre-season, and that's the way we're looking at it.
"We think our last six to eight weeks have been pretty encouraging.
"Last week was obviously disappointing, and that's something we really want to rectify going into pre-season.
"We want our younger players to go into that time with some good belief, rather than a bad taste in their mouth.
"We want to have a strong performance this week to prove that last week was just a little blip.
"We want to earn some respect back from the competition and play for some pride and play for our fans, because they've had a long year like we have.
"I'm sure if you asked them, they'd love nothing more than to go out with a win against Essendon."
