Question marks hover over Rapana's name as Raiders coach Ricky Stuart prepares to name his side on Tuesday ahead of a clash with the Penrith Panthers in Wagga Wagga on Saturday.

The star flyer went for scans on Monday afternoon after coming from the field with a rib issue during Canberra's clash with Manly Warringah over the weekend.

Stuart had hoped Rapana had avoided a break and had only suffered cartilage damage which could have seen him free to line up against the Panthers.

Canberra have the depth to cover Rapana if he is ruled out after Michael Oldfield returned to the fray for Mounties in the NSW Cup.

Oldfield played 30 minutes in his reserve grade return following a groin injury which has hampered his start to the 2019 campaign, before putting in an 80-minute shift at Brookvale Oval last week.

Bailey Simonsson is also waiting in the wings, having scored a try on debut in round one before Rapana made an early return from a shoulder injury.

Both Oldfield and Simonsson have enjoyed success at first grade level in their limited opportunities but losing Rapana would be a cruel blow for the Raiders.

Stuart has no doubts about his side's ability to bounce back from the Sea Eagles defeat, during which a makeshift right edge was tested by the Manly attack.

"They came down that edge a fair bit but we held them out for most parts, they got us on the back end of the first half and then once in the second half," Stuart said.

"It's not going to be the only game we lose. I've been asking the boys to handle the last month with winning games, now we've just got to handle this now together.

"People probably think it's coach-speak when you talk about a week at a time, but it is. We'll just keep our heads down and keep thinking about the next game, we don't look too far ahead."

Canberra's foray into the Riverina has been months in the making with this week's clash to be followed by a return to Wagga next season.

Raiders captain Jarrod Croker has already outlined his desire for a longer partnership to be struck as the club continues to service country NSW regions.

The Penrith clash is Canberra's final tune-up before a blockbuster fortnight against fellow top four residents in the Sydney Roosters and South Sydney Rabbitohs.

It shapes as one of the Green Machine's toughest tests of the season to date as they look to build a case for a long-term place in the NRL's top four alongside those competition heavyweights.