Peter O'Mahony has admitted Ireland failed to cope with England squeezing Joe Schmidt's game plan in 21-13 Twickenham defeat.

Munster flanker O'Mahony conceded Ireland must quickly solve problems that have dogged them in defeats to Wales and England in time for the World Cup opener against Canada on September 19.

England suffocated Ireland from the off in the final World Cup warm-up, hassling head coach Schmidt's men out of their stride enough to set their victory bedrock.

O'Mahony accepted Ireland failed to respond once backed into a corner, but vowed there will be no repeat once Pool D swings into action in two weeks.

"I think any international match is going to be tough, they are going to come at you where you're weak or where you're strong," said O'Mahony.

"We could have dealt with it a bit better though to be honest. These are the things we have to work on, and you've got to expect they'll happen.

"We wouldn't get carried away with one game, we've had a big 18 months and we can take a lot of positives from that. I thought we looked dangerous in attack, maybe we lacked a bit of accuracy, dropping balls in good positions which is uncharacteristic.

"We're still building, we've got two weeks now to rest and get back to the drawing board and make sure we're ready for Canada. We've got to mind the ball, you want to hold on to the ball to be effective."

Ireland looked undercooked in a lacklustre and error-strewn first half against England, Jonny May and Anthony Watson claiming the tries that eventually stole the contest.

Only profligate England attacking let Ireland off the hook of conceding a hatful of points, and taskmaster boss Schmidt will no doubt whip his men back into shape on the training ground this week.

Ireland will be fully expected to ease past Canada, Romania and Italy to set up a Pool D decider against France, but O'Mahony trotted out the well-worn party line in refusing to plot his side's World Cup course.

It could have been captain Paul O'Connell talking when O'Mahony vowed not to look beyond the Canada clash. In fairness to the gritty back-rower, however, Ireland coach Schmidt's training sessions are so intense that errors are not well tolerated.

So after two straight defeats, the Ireland squad can expect some exacting challenges from their Kiwi coach this week.

"Something that's stood to us over the last 18 months is that we've taken it game by game, we haven't got ahead of ourselves, we haven't looked down the line," said O'Mahony.

"We go from training session to training session almost, rather than game to game. We'll focus on Canada for the next couple of weeks and we won't be looking past that."