Those performances saw Ospreys finish third in the GUINNESS PRO12 table and narrowly miss out to Munster in the play-offs.
And Davies believes that the understanding between the half-back duo is such that Warren Gatland's team can reap the rewards from the time spent on the pitch together in the GUINNESS PRO12.
"They do work really well together," said Davies.
"Having a partnership at regional level helps, but with Dan and Rhys they have spent their entire senior careers together stretching back to under-20s level, when I was in the same squad as them."
"They have a bit of a sixth-sense thing going on. They understand what the other is going to do next and react accordingly.
"Both of them played well last season and I'm sure they'll carry that form into the World Cup."
While the pair will be favourites to take the No.9 and No.10 jerseys for Wales, Davies is sure that neither man will be taking anything for granted.
"Dan and Rhys will know they can't rest on their laurels," he added.
"No-one will feel sure of a spot in the side. It is great for the coaches that there is such competition."
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