Eddie Jones believes England must win the physical battle if they are to emerge victorious from their pivotal Six Nations clash with Wales on Saturday.
England head into the game on top of the Six Nations table with three wins from three but Wales are just one point behind and can leapfrog their neighbours with a win at Twickenham.
Jones knows Wales will attempt to physically overwhelm England, with Warren Gatland warning earlier this week that George Ford can expect to see plenty of 17-and-a-half-stone first centre Jamie Roberts.
"Warren's teams have traditionally played gain-line rugby and it's going to be a battle for that gain line. We have one of the best referees in the game in Craig Joubert who likes fast ball," Jones said.
"Wales are probably the fittest side in the competition, or they think they're the fittest side in the competition.
"They base their game on physicality and they've got a clearly understood playing style. They've been together for eight years and they know what they're doing.
"They've got some good Lions players, quality players. They bring solidness to their team and that's why they're always in games of rugby.
"If you look at the World Cup, they were the European team who came closest to progressing to the semi-finals.
"They put in a very good performance against South Africa, so they bring those qualities.
"Welsh rugby is buoyant; they'll be flying down the M4. Jamie Roberts is leading the charge now so George Ford is going to poke himself in front of the M4."
A win on Saturday would offer some measure of redemption for England for their harrowing 28-25 loss to Wales in the World Cup, which contributed to them becoming the first ever tournament hosts eliminated in the pool stages.
Thirteen players survive from the match-day 23 selected against the Welsh on that occasion, but Jones insists this is a different England team who will not be motivated by thoughts of revenge.
"It's 100 per cent realistic to ignore what happened at the World Cup. We haven't spoken about it once because it's irrelevant to this group of players," Jones said.
"This group of players trains differently and thinks differently about the game. We've all had games in the past where we've been scarred.
"I've been scarred by games in the past as a coach, but if you carry those you don't stay involved in high-level sport because you carry baggage around.
"If we need that World Cup game to motivate us, then I've done a bad job during the week. We're a different team. They (Wales) might be the same team, but we're a different one."