Darwin was ruled out of the clash with a serious neck injury that he picked up following a collapsed scrum during the Wallabies' semi-final victory over the All Blacks last week. He was stretchered off the field and lost feeling in his limbs for two minutes.
It was later found he had a prolapsed disc in his neck – possibly a career-ending injury.
"As a front row forward you worry about these things and I was concerned when I saw him go down on TV," said Vickery.
"I'd just like to wish him a very speedy recovery. We all hope he gets back safe and sound."
Vickery will do battle with Darwin's Brumbies team-mate, Bill Young, in the front row on Saturday, but the Gloucester tighthead is doing his best not to get too excited by the enormity of the occasion.
"It's the biggest thing in the rugby world that you can be involved in," he said.
"It's important that we don't get carried away with all the hype and let it affect our preparation.
"Everything now is about preparation and focusing on the game. If we get that right, I'm sure we'll go out and perform."