TOKYO, 1 Nov - Sam Underhill is ready to fight fire with fire against South Africa on Saturday - but insists it must be controlled aggression from England.

The powerful Springboks have named just two backs in their eight replacements, which means they can bring on almost an entirely new pack to ensure their forward challenge remains formidable.

England have gone for the more traditional three backs and five forwards to supplement the starting XV and hope to use flankers Underhill and Tom Curry to secure quick ball and keep the opposition on the move in defence to tire them out

It is the tactic that paid off so well against New Zealand, where a 19-7 semi-final win was built on quick ball and incisive running from the England backs.

Underhill, above, will have a key role against the Springboks and has to negate their big, physical forwards at the breakdown.

He said: "They are a pretty big side across the board, with some good ball carriers. They are a big threat at the breakdown with guys who get over the ball and against Wales they counter-rucked pretty well. Physically, it is important we turn up.

"It’s important in our attack to have speed of ball, and that’s what the opposition don’t want. For any attack to function well you need good speed of ball. In defence there’s not much you can do apart from turn up physically.

"That’s probably going to be a theme going into tomorrow, a lot of what’s underpinning a lot of the game is physicality. Get that right and hopefully we will be able to dictate the game.

"It’s all very well being aggressive but the key is to have control of that and still do what you want in the game outside of just being physical. Last weekend has probably given us more confidence and probably brought us together as a team.

"They (South Africa) are a different side to the All Blacks, probably a bit more direct, more set-piece focused, something they pride themselves on. Physically, it is going to be a big part of it and we need to be accurate in what we do."

Second-row George Kruis, meanwhile, believes the experience of his fellow Saracens players in the England squad will help. They have won major trophies domestically and in Europe, and Kruis said: "There is definitely an understanding of nerves and how you deal with them a bit more.

"I remember my first final, you definitely overthink a lot of stuff. You try to get everything perfect but you just have to get your processes right. You don’t have to overthink things.

"We have to see it as just another game and make sure that mentally it doesn’t get to us. That is a learned thing but we’ve done a lot of work to build up to these moments. We’ve dissected previous games where there have been some issues.

"We’ve seen the progression. It has been brilliant because we’ve really put some work into it."

Kruis is also using England's failure to get out of their pool as World Cup hosts four years ago as inspiration.

"A lot of good teams, teams who have won things, have lost or gone through learning phases previously," he added. "Although that doesn’t give us any right for tomorrow - we have to turn up and do the job - it definitely helps that a lot (of us) went through the pain of losing and learning from that.

"It doesn’t mean we are owed anything but it will go towards making a difference tomorrow."

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