The mental maturity and ability to compete under pressure that has come to define the Raiders early this season was evident between the 18th and 28th minute of their win over Penrith in Wagga.

On the back foot for most of the first half and having lost fullback Charnze Nicoll-Klokstad to the sin-bin for a professional foul and then star forward John Bateman to injury, Raiders teams of the past two years would have succumbed to the pressure.

Instead the Green Machine's defensive line held firm as they earned a 14-0 lead at the half-time break, a buffer they would not surrender as they secured their sixth win of the season.

"I reckon that wins us the game today," Canberra coach Ricky Stuart said of his side's effort during Nicoll-Klokstad's time in the sin bin.

"I thought we started the second half flat and you get a bit concerned with that, so we have to get better there.

"But we got through some adversity with our injuries and then we've had John Bateman have to go off and changes in the outside backs because of BJ [Leilua, who was a late withdrawal due to a neck issue].

"So, it was a really tough win and those are the wins that count at the end of the year."

The win might come at a serious cost with Bateman sent to Wagga Wagga hospital for scans on a potentially fractured eye socket after he recoiled out of an attempted tackle on Viliame Kikau.

Stuart said the loss of Bateman even if for one week would be acutely felt by the team given what he's added to Canberra this season.

"He's not going to be there every game through his time here, so we've got stand up like we did today [without him]," Stuart said.

"Individuals have to stand up like they did and take responsibility. Elliott Whitehead was one of them, Josh Papalii and Ryan Sutton stood up and took their game to another level because they knew Batty was off."

Leilua is likely to come back into the side last weekend at the expense of Michael Oldfield, who scored the first try of the day and was as consistent as always despite the late-call up.

"He was playing, he was this morning," Stuart said of Leilua's withdrawal.

"He's had a crook neck during the week but he went into spasm last night and he didn't get much sleep, we worked on it and it didn't come good.

"It was a good lesson for blokes that are 18th or 19th man for them to prepare to play and that's why Michael Oldfield, who's a very experienced player, did a really good job knowing he was going to be starting today."

The Raiders' premiership credentials will get a serious test over the next fortnight as they face the Sydney Roosters and South Sydney Rabbitohs, a challenge Stuart said his men are looking forward to.  

"It's that period of time where there's a bit of separation between the bottom four and the top four and it's important doing everything you can to win," he said.

"The feeling in the change rooms today is the reason is you get so shitty after a loss because you want those wins."