And Gatland is pleased he has managed to accommodate two of Wales' most promising attackers in the same team.
"We are trying to get one of our best players on the field in James Hook," he said.
"We were really impressed with Rhys in the first couple of warm-up games (against England), and we felt that combination with James at 15 and having two attacking players at first receiver, with James being able to do that as well, gives us an opportunity.
"Rhys has confidence, he has got a very good balance in his game. He is an effective runner, has a good boot on him and he has that self-belief you look for as a coach."
In the pack Newport Gwent Dragons second-row Luke Charteris was named ahead of Bradley Davies and Gatland says he has picked on form following the warm-up fixtures.
"It was a close call between the second-rows, but I think at the moment Luke is our number one. He played really well against England," he added.
"He's in great shape, and the way he has improved in the last few months has been outstanding.
"In the past he has had injuries and hasn't always been able to take a full part in training, and it has been difficult for us to select him.
"But I think he has missed one session in two months. We have been really impressed with him."
WALES: James Hook; George North, Jonathan Davies, Jamie Roberts, Shane Williams, Rhys Priestland, Mike Phillips; Paul James, Huw Bennett, Adam Jones, Luke Charteris, Alun Wyn Jones, Dan Lydiate, Sam Warburton (C), Toby Faletau
REPLACEMENTS:Lloyd Burns, Ryan Bevington, Bradley Davies, Andy Powell, Tavis Knoyle, Scott Williams, Leigh Halfpenny