Cardiff take on Scarlets in the east versus west clash at BT Sport Cardiff Arms Park in the first of three crunch festive derbies for the Blues.
Mark Hammett's men sit ninth in the GUINNESS PRO12 table, two places and ten points behind the west Wales outfit, but will be looking to overhaul Scarlets in their quest to qualify for Europe's top competition.
And 25-year-old Dacey, who has replaced captain Matthew Rees as hooker for the showdown, admitted a good result could set up a run of Christmas form.
"Anything less than a win and we have let ourselves down," he told WalesOnline.
"On paper they're a very good side. I don't think they've performed to the best of their ability so far this year.
"Scarlets is absolutely massive for us because when you play against another Welsh region it always has that added spice.
"As a player you should treat every game as the biggest of the season and that's the mentality we need to have going from game to game.
"We have got a lot of international boys here and a lot of youngsters striving to achieve those honours.
"I don't know whether the boys find Europe more of a motivation, but there's no reason why we can't get there
with the firepower we have got here.
"So hopefully we can produce some good performances over the coming weeks."
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