Wales face up to the All Blacks on the back of two disappointing performances against Argentina and Samoa.
And Roberts acknowledges Wales have fallen well below the expectations they set themselves so far this autumn but believes a game with the World Cup champions could be just what they need.
After struggling with a groin injury for the last two weeks, Davies comes in for Ashley Beck to partner Roberts in the centre.
“I’ve got very fond memories of playing with Jon and the Grand Slam was very special for both of us,” said Roberts.
“He’s a very talented player, a very good defender and a direct player as well. He’s great to play alongside and hopefully we can rekindle the form we showed in the Six Nations.
“It’s great to have him back, competition in midfield is driving everyone on to their best rugby and that’s what it’s about.”
Following Friday night’s defeat to Samoa, the Welsh squad have come in for criticism from a number of quarters. And Roberts admits it’s been a difficult time for everyone involved in the squad.
“It was a tough weekend and a lot of people were asking what’s going on but there’s no one hurting more than the players,” added the Cardiff Blue.
“We’ve set a benchmark of performance and to come under that quite significantly in the last two weeks has been hugely frustrating.
“We need to pull together as a group and there is only one group who can turn it round and that’s us. There is no magic wand so it’s important we get back to training and prepare for this weekend.”
This weekend sees Steve Hansen return to Wales as New Zealand’s head coach and while the All Blacks will provide the ultimate test, Roberts is welcoming the challenge.
“To play against the best side to have played the game is what we need,” Roberts argued.
“The chance to take on the All Blacks is magical really. When you play against England it’s pretty special but when you play the All Blacks it’s a very, very special game, it’s a unique experience.”
Asked how his side will go about taking on Hansen’s side, Roberts had one answer.
“I think you have to play rugby against these guys, you can’t afford to tighten up your game,” he said.
“We need to go out there and play a brand of rugby which we know we can play.
“The Welsh teams in the past who have come close at the Millennium Stadium have gone and played. You have to match them physically, defend as a unit or these guys will cut you to shreds.”
The All Blacks have been in devastating form on their tour of Europe so far, running in six tries in a 22-51 win over Scotland before easing to victory over Italy in Rome last Saturday.
And Roberts knows the extent of the challenge facing his side.
“Their breakdown work is second to none and defences aren’t given much time to reorganise,” he said.
“They’re always playing on the front foot and they play percentage rugby. They can chop and change their team every week and they’re still up there with the best teams in the world.
“Full focus for 80 minutes against these guys is paramount.
“Switch off for one second and you’re under your posts.”
