Navidi touched down twice during a first half that the Blues dominated, while Gareth Anscombe kicked 11 points before the break to eventually secure a 21-9 win against their Welsh rivals.
Momentum has been something the Blues have lacked all year in the GUINNESS PRO12, their victory on Friday night the first time they have won back-to-back matches in the league this season to leave them ninth.
But with consecutive fixtures against Newport Gwent Dragons to come on Boxing Day and New Year's Day, Navidi believes the efforts of the front five will prove crucial to any success.
"The front five were outstanding and built a good platform for me at the back of the scrum and the driving maul was going well so we just need to keep going and have a good run over Christmas," said Navidi, who was named man of the match at BT Sport Cardiff Arms Park.
"We didn't hold onto the ball long enough in their half during the second half and that is a key area we need to improve.
"But we came out with a win, we didn't get any points in the second half which is disappointing, but we move on now and look to get another."
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