Tom Wood has admitted that he will have to be at his best to be successful against Dan Lydiate when England meet Wales at Twickenham on Saturday.
England kicked off the World Cup with a 35-11 triumph over Fiji last Friday, and Stuart Lancaster's side will be confident of reaching the quarter-finals if they can claim another win against their Pool A rivals.
However, Wood is looking no further than his clash with Lydiate as he tries to win their personal duel.
"He's a big old lump," Wood told reporters. "He provides some ballast in the close exchanges. He's got a particular style of tackling technique that is very difficult to navigate.
"He chops you down at about knee-height and it's very difficult to get any leg-drive through a tackle like that. He gets horizontal early and gets hold of you."
Wales started their tournament with a 54-9 win over Wales on Sunday.