The European champions took a while to come to the boil in their round robin opener and first Olympic game together, with Italian skip Joel Retornaz scoring two in the first end.
But they soon warmed to their task, with Mouat and vice-skip Grant Hardie, from Dumfries, both shooting 90 per cent to open up with a confident victory.
“We’re happy to get that first win because they are a really good opposition,” said Mouat.
“We had to grind into it. It was a wee bit of a slow start and they kind of put us on the back foot but we stuck together and played a lot of really good shots to get back in the game.”
A steal in the eighth end helped Mouat, Hardie, Bobby Lammie and Hammie McMillan dictate terms down the stretch and they laid one in the last to sweeten the scoreline.
Mouat narrowly missed out on a mixed doubles medal with Jennifer Dodds, beaten in the bronze medal match by Norway.
The 27-year-old clearly got a kick out of being back with his regular team-mates and was delighted to put Tuesday’s defeat behind him.
“Tuesday was a bit of a tough day but this is the team that I’ve played with for 95 per cent of my time in the last three years,” said Mouat.
“This is the one I’ve always looked to and always felt that this is the one I want to win. It would have been nice to win the other one, but I just think that I wanted to turn it around and play well for the boys as well as myself.
“Getting back onto the ice and feeling at home with the boys again was nice. I’ve not really seen them for quite a while.
“It was really good to be making a lot of shots and having my sweepers back which was very nice!”
It was a special day for Olympic debutant Lammie, also from the region, the youngest member of the rink, who celebrated his 25th birthday with a victory at the Ice Cube.
It’s USA and Norway up next for the world silver medallists but not before Lammie has revelled in the rest of his big day.
“I think that’s probably up there in terms of birthday presents, that’s the top one!” he said.
“You can’t ask for much more than a win in your first Olympic game. I might hit up Pizza Hut or KFC to celebrate we’ll see.”
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