"Let's hope we get 21." That's Canberra Raiders coach Ricky Stuart's reaction when he heard about the magic number that could decide his team's NRL finals future.

This season the Raiders are unbeaten when they get to 21 points, but are also yet to win a game where they score less than that mark.

If the Raiders can score 21 or more against the Penrith Panthers in their knockout semi-final at Canberra Stadium on Saturday night then statistics show they'll be very hard to beat.

They're the NRL's most potent attack and have scored points seemingly at will throughout the season, but when the opposition has been able to restrict their scoring they've struggled to get over the line.

That free-wheeling attack played a large part in the Raiders stringing together 10 consecutive wins to end the regular season in second on the ladder.

During that run they were also able to show how miserly their defence can be, with especially good efforts against the Melbourne Storm and Cronulla.

But Stuart wasn't too worried about statistics and said there was only one that mattered – the scoreboard.

"Let's hope we get 21," he joked when asked about the magic number.

"I don't jump into the stats too heavily. We're in a position where we need to score more points than the opposition – it's as simple as that."

The Sharks were able to restrict the Raiders to 14 points in the qualifying final to sneak home with the win.

But the Raiders had their opportunities in the first half and could have easily scored four tries and passed the 21 mark to blow the Sharks away.

It was something Panthers coach Anthony Griffin was mindful of, especially given the greasy conditions for the Canberra-Sharks clash.

In contrast, the Panthers blew the Canterbury Bulldogs away in their elimination final on Sunday in perfect conditions for football.

With weather in Canberra likely to be similar to last weekend, Griffin said the Raiders would be one step ahead with adapting to the conditions.

But he wasn't getting lulled into a false sense of security about the low scoring nature of the Raiders-Sharks final.

"I didn't think they were that quiet. Because it's a final, the scoreboard's just not going to tick over because you're in possession," Griffin said.

"Cronulla are a great defensive side. I thought [Canberra] played a really good 40 or 50 minutes of football and then they lost their hooker and playmaker [Josh Hodgson to an ankle injury] and a few things went their way.

"Then they got done in the last couple of minutes by a penalty. I thought they were very good. We're going to have to be a level up on last week if we are to go with them."

NRL SEMI-FINAL

Saturday: Canberra Raiders v Penrith Panthers at Canberra Stadium, 7.45pm. Tickets available from Ticketek.

Raiders team: 1. Jack Wighton, 2. Edrick Lee, 3. Jarrod Croker, 4. Joey Leilua, 5. Jordan Rapana, 6. Blake Austin, 7. Aidan Sezer, 8. Junior Paulo, 9. Josh Hodgson, 10. Shannon Boyd, 11. Josh Papalii, 12. Elliott Whitehead, 13. Sia Soliola. Interchange: 14. Kurt Baptiste, 15. Luke Bateman, 17. Joe Tapine, on to be named.