Stephen Ferris has warned Ireland that only their best will be sufficient to challenge England at Twickenham in Saturday's Six Nations game.
The sides meet for the climax to the 2012 championship in a contest that is likely to determine who finishes runners-up behind Wales.
"You have to be on top of your game to get a result at Twickenham," said the Ireland flanker.
"They won't concede any soft tries, like Scotland did, either."
England produced a superb display to beat France 24-22 in Paris on Sunday but Ferris added that the Irish will also head to Twickenham in confident mood after Saturday's 32-14 win over Scotland.
The English will clinch the title if France win in Cardiff earlier in the afternoon and Stuart Lancaster's side can claw back a points difference of 38.
"We are improving week on week and are happy with our set-piece, but we know England are strong there," added Ferris.
"We have to chase the box-kicks down hard and get behind them. Rob Kearney is going to be busy in the air again."
Ferris was in inspirational form once more, producing a string of magnificent tackles against Scotland in a typically aggressive defensive shift.
Ireland's defending has been unrecognisable from the passive display seen on the opening weekend against Wales and Ferris is pleased with the progress made.
"In the last couple of weeks I've done a bit more defending than I would have liked but that's the way it goes," the 26-year-old said.
"I've put my body on the line and got into the defensive line, reading it well.
"Overall we defended well and apart from that soft try Scotland didn't look like breaking us down.
"Since the criticism we took after the Wales game we've defended pretty well."
Ferris praised the performances of Munster duo Donnacha Ryan and Peter O'Mahony, who replaced the injured Paul O'Connell and Sean O'Brien against the Scots.
"Donnacha came in and took over the lineout, he had an awesome game. He's very calm and cool, nothing seems to faze him," he said.
"Peter was great. There's a bright future for him. He likes to get stuck in. He's typical Munster - as hard as nails."