Ireland are hoping to take a significant step towards repeating their RBS 6 Nations title triumph of 2009 when they host the championship favourites at Aviva Stadium on Sunday.
"Brian's been great to play with for all these years. We've been in and around teams together since we were 16 or 17," he said. "We've always played together and he's so easy to play with, whether it's in attack or defence. One of the things that stands out for both of us is that we enjoy tackling and the confrontation."
He added: "We have the chip on our shoulder that you need to be a really good defender.
"That was epitomised last Saturday when Brian stopped one of Wales' second rows dead in his tracks five metres from our line.
"When you see stuff like that it's inspiring in its own right.
"A mantra in this squad is 'no matter what it takes to get it done, just do it'. That's come across in the way Brian and I have played down the years."
D'Arcy is expected to recover from his dead leg in time to feature in the starting XV named on Friday, and line up alongside O'Driscoll in midfield for a 48th Test.
- Sports & Recreation