Bateman and fellow Englishman Ryan Sutton are considered key signings for a Raiders side that's lost some serious size up front since last year.

Gone are big men Shannon Boyd and Junior Paulo, while five-eighth Blake Austin is another to have farewelled the club over the summer.

Bateman will compete with Whitehead, a former teammate at Bradford between 2009-13, and Joseph Tapine in what shapes as an intimidating forward pack.

Bateman, who has spent the past five years with Wigan, and Whitehead started as the back-row combination for England during their Test series against New Zealand late last year.

"Look he's very competitive. If you've watched him playing Super League, especially international-wise, he don't wanna lose," Whitehead told reporters on Wednesday.

"He's got that bit of grubby side about him as well. He's a tough kid, he's from one of the roughest estates in Bradford - he won't mind me saying that.

"He's a very talented player as well. Even when we were at Bradford, I knew he always had that talent. And moving to Wigan, I think it really upped his game.

"And I think moving over here to Canberra is going to do that to another level as well."

The additions of Bateman and Sutton bring the Raiders' contingent of English players to four, including new co-captain Josh Hodgson.

Having long harboured a dream to play in the NRL, the 25-year-old admitted the familiar faces were a factor in deciding which club to join.

"That's what I took into consideration moving here," Bateman said.

"It's a massive move moving to the other side of the world. When you don't know anyone it makes it even harder but obviously knowing Elliott and Hodgy, it's been really good for me."

While the Raiders lose grunt without Boyd and Paulo, both of whom were released early from their deals, Whitehead says the team will be more mobile.

"It's a little bit different from the last three years I've been here. We've maybe lost a bit of size and got a bit more agility," he said.

Australian Associated Press