The Raiders' opening two performances in 2018 have again raised questions about their ability to close out games; both matches resulting in two point losses after they'd held good leads.

In 2017 Ricky Stuart's side dropped eight matches by six points or less.

Whitehead admitted the Raiders' defence needed to improve after identical 30-28 losing scorelines against Gold Coast and Newcastle.

"We're still confident in the ability in the squad and what we're capable of," Whitehead said on Tuesday.

"We looked at video today and there's just areas in our defence letting us down."

But in better news for the Raiders, their injury concerns aren't as bad first thought.

Former Dally M centre of the year Joseph Leilua has been named in Canberra's team to take on the Warriors at GIO Stadium on Saturday.

Stuart said it wasn't "looking good" for Leilua after he was taken off on a stretcher with an ankle injury against the Knights.

But fears of any serious damage proved to be unfounded and Leilua will attempt to get up for an unlikely appearance with a six-day turnaround.

Whitehead also received treatment on his back late in the game, but he has been named at No.12 and said he "should be right" to take his spot.

However, fellow forward Charlie Gubb has been ruled out of facing his former side after suffering a groin injury in his Raiders debut.

But with Gubb's misfortune comes an opportunity for former Manly and Sydney Roosters prop Liam Knight.

A start for Knight would add to his sole NRL appearance for the Sea Eagles in 2016 after being named in Canberra's 17.

"Liam works hard at training and he's been going really well at the (feeder club) Mounties," Whitehead said.

"If he does make his debut, he'll be one to watch out for."

Australian Associated Press