Fittler, whose team's other four-pointers came from centre Chris Lawrence and fullback Lachlan Coote, also praised hooker Robbie Farah's eye-catching display.
"It was real mature win and Robbie and Mitchell were fantastic at controlling the result,'' Fittler said.
"We relied on them to win the game. They both played a part in our kicking game and exposing their weaknesses.
"I thought everything that was asked of Mitchell leading into this game he answered. He had a couple of good runs, his passing was slick and you couldn't really ask much more from him.''
Daley said Carney was ready for his long-awaited NSW debut, but warned the Cronulla man he needed to perform for 80 minutes.
Carney was a peripheral figure in the first half, but produced a moment of pure class to leave Jamie Buhrer for dead with a side-step and inside pass for Tariq Sims to score his second try.
"He started slow, Toddy, but was good for us in the second 40,'' Daley said.
"You need to get on the front foot in Origin and, if you are doing the little things well, points will flow from that.
"The players that have been there know what is required at Origin level and the other guys that haven't been there can get a small taste of what's required here and that is why this game is important.''
Carney agreed with Daley that he needed more work on his game before he could play Origin, but said he hoped he'd done enough to convince NSW coach Ricky Stuart to pick him.
"I know there is more I can do,'' he said.
Hayne did little to suggest he was a genuine No.6 and finished the game on the wing after an injury-enforced backline reshuffle and also threw an intercept pass for one of Blake Ferguson's two tries for Country.
Pearce was satisfied with his performance, but admitted he needed to continue at the same level for the Roosters to and ignore calls for Peter Wallace or Jarrod Mullen to wear his Blues No.7 jersey.
"I hear something different every week, but I was happy with my game and that is all I can do,'' he said.
"I don't think my form has been that bad this season, but I enjoyed playing with Robbie and I think we compliment each other well.''
While Country were gallant, Daley conceded his side gave themselves too much to do after letting City rack up a 24-point lead before halftime.
City centre Joseph Leilua was placed on report in the first half for a chicken wing tackle on Ferguson.