Defending women’s champion Eve Muirhead, however, had earlier relinquished her title following an extra-end defeat to Switzerland’s Silvana Tirinzoni.
Edinburgh’s Mouat and his team-mates Hammy McMillan, Bobby Lammie and Grant Hardie had already beaten Joel Retornaz 7-6 in the round robin section on Tuesday and they once again had to go to an 11th end to get the better of the Italians.
The Scots overturned an early 3-1 deficit to lead 6-4, but Retornaz counted two stones at the last end to extend the semi-final to a winner-takes-all decider.
As on Tuesday, Mouat held his nerve and nicked a three to win 9-6.
“The Italians have been hot all week and have played a lot of great shots, but we were determined to repeat what we did against them on Tuesday,” said Mouat.
“From 3-1 down, we put together a few really good ends and started to control the four-foot and make Joel play a lot of tough shots. I was just relieved that he didn’t get a three at the tenth end. When it went to the extra end, we had the hammer [the last shot] which is what you always want. It was a textbook extra end we played with everybody doing their job and me making the last shot for a three and the win.”
Edin beat German Marc Musakatewitz 6-3 in the other semi and will be bidding for his fifth European gold in a row tomorrow.
Muirhead and her colleagues Lauren Gray, Vicki Chalmers and Jennifer Dodds knew that a spot in today’s semi-finals would be theirs if they beat Switzerland and Germany lost to world champions Sweden.
Part two of that equation worked out perfectly, but Muirhead narrowly failed to keep her side of the bargain.
The Scots trailed 3-2 after six ends before counting a two at the eighth and a single at the next to lead 5-3 going to the final end.
Tirinzoni drew level as she chased a clean sweep of nine round robin victories, but Muirhead had the advantage of playing the last shot at the 11th end.
The Swiss put three stones in the house and Muirhead was unable to find a way past with her final delivery as Tirinzoni scraped home 6-5.
For the first time since 2009, Muirhead has missed out on a European medal, but it was only her fourth tournament following career-saving hip surgery in May and, in the final analysis, three single-point defeats proved fatal.
However, finishing fifth-equal with Latvia at least qualified Scotland for the World Championships in Denmark next March.