Let's face it, he's a lock for that given his form this season for the Green Machine in the NRL.

Lock's also the position Raiders coach Ricky Stuart has moved him to as part of a revamped forward pack that's started to dominate teams in the run home to the finals.

Canberra's on a three-game winning streak, but they need to double that to make the top eight with Sunday's clash against Penrith at Canberra Stadium a massive one in the context of their finals hopes.

Whitehead played most of his England Super League career in the second row, with a few games at centre for Bradford and Catalans, but Stuart has utilised his versatility since arriving in Canberra.

He's played at five-eighth with a few stints in the centres on top of a majority of his time in his usual spot on the edge.

But he's been at lock in the last two games - wins over Cronulla and the New Zealand Warriors - where he's starred with his work ethic and ability to play 80 minutes.

Later in the year he'll be a crucial cog in England's World Cup campaign, but given their depth in the middle the 27-year-old wasn't expecting he'd be needed there.

"I'm not sure, I've played back row all year so I'd expect to be playing back row for England come the end of the year," Whitehead said.

"We've got some great forwards that play for England, like Sam Burgess, the Burgess boys, James Graham that play over here. There's also some great forwards over in Super League that can fill the middle spot.

"I reckon I'd play back row if I got selected for England, but that's up to Wayne and I have to get selected first before anything."

While Whitehead's happy to play anywhere, his preferred spot is in the second row where he'd formed a potent combination with the "Leipana" bromance of centre Joey Leilua and winger Jordan Rapana.

But he's been enjoying getting his hands on the football a lot more since his shift from the right edge.

He's averaging 82.9 metres per game for the season, but that's jumped to 131m since his move to lock.

To say he's simply had to adjust to a switch from the edge to the middle doesn't tell the full story, with injury and sin bins seeing him shift back to the edges at either centre or second row at times in the last two weeks.

"???I'm becoming used to it now. The last two weeks I've probably played four different positions," Whitehead said.

"I started middle against the Sharks and then went to left back row, right back row, right centre.

"And last week I did the same as well - I went from middle to right centre - so I'm getting used to it now. Hopefully I can keep a spot now because keep getting moved around ... that's what I don't want to be [doing]."

Raiders chief executive Don Furner said the proposed salary cap of $9.4 million, including an optional $200,000 veteran-player allowance, gave welcome "extra room", but he said he wouldn't know until the end of the year as to where they stood in terms their roster and whether they'd have to release any players.

"We're happy that it's gone up a little bit, but that's not finished yet so we'll see what happens," he said.

"We're always happy that there's extra room, but you just don't know where the season will end up. With rep footy a lot can happen and we'll assess it all at the end of the year.

"Obviously we were happy with the compromise. It's a good deal, hopefully [they sort out] the other issues and get the deal done before the end of the season."

NRL ROUND 24

Sunday: Canberra Raiders v Penrith Panthers at Canberra Stadium, 2pm. Tickets available from Ticketek.

Raiders want: Cronulla to beat the Cowboys on Saturday and Canterbury to beat Manly on Sunday.

Raiders: 1. Jack Wighton 2. Nick Cotric 3. Jarrod Croker (c) 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. Joe Tapine 13. Elliott Whitehead. Interchange from: 14. Kurt Baptiste 15. Clay Priest 16. Dave Taylor 17. Luke Bateman 18. Michael Oldfield 19. Jeff Lima.

Panthers: 1. Dylan Edwards 2. Josh Mansour 3. Tyrone Peachey 4. Waqa Blake 5. Dallin Watene-Zelezniak 6. Matt Moylan 7. Nathan Cleary 8. James Tamou 9. Sione Katoa 10. Reagan Campbell-Gillard 11. Corey Harawira-Naera 12. Isaah Yeo 13. Moses Leota. Interchange from: 14. Tyrone May 15. Bryce Cartwright 16. Tim Browne 17. James Fisher-Harris 18. Trent Merrin 19. Dean Whare.