The visitors came from 12-0 at half-time to win 18-12 at Canberra Stadium on Thursday.

It's the Raiders' third loss in a row with errors again proving costly.

For much of the game it looked like they'd put their ball retention issues behind them, but costly errors in the final quarter helped the Cowboys get in front and them prevented them from producing a comeback of their own.

It meant they couldn't mark their co-captain Elliott Whiteheads 150^th NRL game with a win.

After questioning his own form during the week, Josh Papalii came out breathing fire - running for 113 metres in the first half - the most of any player.

Fellow middles Ryan Sutton and Joe Tapine were also strong as the home side got on top.

Such a focus have completion rates been for the Green Machine this week even the ground announcers had bought in announcing the 77 per cent statistic at half-time - it had been 100 for large parts of the opening stanza, just dropping away towards the end of the 40 minutes.

But that fell to just 72 per cent by the end of the match.

The Raiders came out with clear defensive intent, limiting the Cowboys to about 30 metres on their opening set.

Poor discipline and poor completion have been the bane of the Raiders over the opening five rounds, but they benefited from the visitors' ill discipline - cashing in on early penalty.

With no back-up on the bench, Raiders hooker Tom Starling was again needed to produce an 80-minute performance - something he did last weekend in Wagga Wagga.

He was lively early, darting out of dummy half to shoot across under the posts untouched to open the scoring.

Corey-Harawira-Naera's been forced to show his versatility in recent weeks, with injuries and concussion assessments forcing him into the centres.

But it was his quick hands that were on display with a quick tap on for Jordan Rapana to score in the corner.

Canberra were able to weather several Cowboys forays, but their defence stood firm until the break.

North Queensland were able to cross once, with Kyle Feldt touching down in the corner, but Jeremiah Nanai obstructed in the build up.

Nanai had a dirty first half, with that offence being one of four penalties he gave away.

The Raiders also had a try disallowed, with Canberra co-captain Elliott Whitehead knocking on while trying to score in his 150^th NRL game.

It was 12-0 at half-time, but the Green Machine probably should've been further in front.

Would that come back to bite them?

The Cowboys scored first in the second half, converting back-to-back penalties into a Heilum Luki try - the second-rower crashing over from close range.

North Queensland enforcer Jason Taumalolo started to get the visitors rolling, but a couple of big Raiders plays helped stop the tide.

Canberra fullback Charnze Nicoll-Klokstad produced a one-on-one strip, then a great team effort forced Tom Dearden back in-goal for a dropout.

But the Cowboys kept coming - especially when Taumalolo returned from a short break.

Valentine Holmes capitalised on a Nicoll-Klokstad error to score under the posts and level the scores going into the final quarter.

Young Raiders fullback Xavier Savage was brought on for Nicoll-Klokstad with about 14 minutes remaining, but he was forced into touch on his first carry.

That turnover led to the Cowboys taking the lead with Nanai turning from villain to hero, getting on the end of a Scott Drinkwater grubber to grab the lead for the first time.

A Harawira-Naera strip game the home side some hope, but they coughed up the ball while pressing the Cowboys' line to end their chances.

AT A GLANCE

NORTH QUEENSLAND COWBOYS 18 (Heilum Luki, Valentine Holmes, Jeremiah Nanai tries; Holmes 3 goals) bt CANBERRA RAIDERS 12 (Tom Starling, Jordan Rapana tries; Brad Schneider 2 goals) at Canberra Stadium. Referee: Ashley Klein. Crowd: 11,854.