However, the 34-year-old could return this weekend to add some composure to the line-out area following last Saturday's 29-23 loss to the Wallabies in Sydney.
Rees has now returned home to be with his wife for the birth of their first child and Davies, having overcome a rib injury, hopes to take an opportunity to shine with the World Cup in mind.
Davies said: "There's always hope and playing for your country is your biggest desire and you always aim for it.
"If you get an opportunity to be in the squad it's the place you want to be and I've been fortunate enough to have a few campaigns with a lot of different experiences.
"During the Six Nations I was there but not involved and felt out of it and wanted more. Then I was selected for the tour and it's exactly what I wanted.
"But unfortunately I had an injury that set me back, then had a second opportunity and I'm grateful for it and hopefully I'll be involved on Saturday."
Yet despite his lack of involvement, Davies feels criticism of the Welsh line-out has been unfair.
He added: "It's easy to criticise and some people are making assumptions, but it's a big-picture environment. If you don't try things, you don't know what the opposition are doing.
"So it's a bit of a game of chess to some extent and it's difficult for the caller to make a decision and you don't know what the opposition are about until you make your first move."