Ireland aren't worn out
Sportal.co.nz 13 Jun 2012 Getty Images
But O'Brien, who was one of the shining lights in an Ireland team that were overpowered 42-10 by the All Blacks last Saturday, rejected the notion that the fixture schedule was too punishing.
"I don't think it is," he said. "We know the schedule. We know we have another two Tests. After that, we can think about holidays or whatever but we have two games to play, two Tests, and we will be going hard.
"It is easy to lift yourself up for the world champions. This is where you want to be and who you want to test yourself against. It gives you a good idea of where you are as a rugby player."
The 25-year-old sat out training in Auckland on Monday as he is on a reduced training programme following surgery on his injured knee in May.
He insisted there was nothing to worry about ahead of Saturday's second Test in Christchurch, though.
"The body is not too bad. I'm getting my recovery done," he said.
O'Brien knows he and his team-mates must be stingier in possession if they are to reduce the gap when the sides meet again.
"They are very clinical," he said. "You can't afford to cough up soft ball to them. We have to be a lot smarter.
"We didn't have the ball for long periods of time and we had to make a lot of tackles in defence. It took its toll on us."
Prop Ronan Loughney, meanwhile, is ready for another taste of Test rugby after making his debut at the weekend.
Loughney made his international debut in Auckland in what was a chastening experience for the side but a day of immense personal pride for the 28-year-old.
Fellow front-rowers Cian Healy (shoulder) and Mike Ross (hamstring) took no part in training on Monday, meaning he is likely to see more game time in the rematch.
Loughney is looking forward to it.
"My debut was an amazing experience," he said.
"It was a lifelong dream to put on the green shirt. Obviously, it was great opposition to do it against. They have been the best team in the world, on and off, for years now.
"It was a difficult result but it is good to get a taste of what that level is like. It is another step up again and I'm hoping to get another opportunity."
Loughney is particularly keen to mix it with All Blacks captain Richie McCaw.
"To be at his level, that is what you aspire to," he added.
"It was a great experience to be playing against him."
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