Wales coach Wayne Pivac says a rise in intensity in training has convinced him his side will produce a big performance against England.
Wales are aiming to bounce back from successive Six Nations defeats against Ireland and France.
"The level of intensity has noticeably gone up in training, certainly in the live stuff and it has been no holds barred," said Pivac.
"No one has been holding back. That tells me a big performance is coming."
Pivac says captain Alun Wyn Jones has been at the heart of the pre-match efforts.
"You've only got to listen to Alun Wyn during the week," said Pivac.
"The intensity is there in his voice and everything he's done in training. He's led from the front."
The physicality has tested Cardiff Blues back-rower Josh Navidi who has been selected at number eight ahead of Taulupe Faletau who has been dropped to the replacements bench.
This is despite Navidi having not played since January after missing the first three Six Nations games with a hamstring problem.
Pivac believes Navidi is key to cancelling out England's physical threat as the coach prepares to make a "few tweaks" to the Wales game plan.
"Josh is a fantastic player over the ball with the breakdown work that he does, his defensive work and ball-carrying," said Pivac.
"When he played for Wales against New Zealand a few years ago, Steve Hansen asked who he was because so impressed with him. He is a tough character and is someone that puts a lot of pressure on the opposition.
"If you look at the Six Nations match against England last year he played a massive role in that win for Wales and he plays well in big games.
"He's stood up and played in some very big matches for us, so we're confident he can do that again."
Pivac is preparing for his first Wales and England affair and is aware of the magnitude of the occasion.
"With my background coming from New Zealand we look at England like the Welsh do," said Pivac.
"They're a strong team, one of the world leaders, and a very capable team as we saw at the World Cup against the All Blacks and last week against Ireland. They put away two of the top teams in the world comfortably.
"There is a healthy respect, but it's a game we're looking forward to. Me included."
Wales are aiming for a first Six Nations victory in Twickenham for eight years with England coach Eddie Jones only suffering two losses and a draw in 26 home matches since 2016.
"Clearly they've got a great record there and one we respect," said Pivac.
"It is one which tells us we'll have to be at the peak of our powers to win."
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