O'Brien missed the win over Scotland with a foot infection but will start the final game of the 6 Nations in place of Peter O'Mahony who drops to the bench, with Shane Jennings missing out altogether.
But while O'Brien was the main focus of selection talk in the only change to the Irish side, it is Ferris' comments on Anglo-Irish rivalry that have been making the headlines.
"Ask any team who they like beating and it's always the English," said Ferris, who has started all four games in this year's tournament but missed training yesterday due to an ankle problem.
"Why? It's something I can't really put my finger on.
"We took so many beatings from England at under-age level. Any time we played Under-18s, 19s or 20s we always received a thumping. I never beat them.
"They come with bit of a tag about being arrogant and if you asked any team they'd probably say the same thing. They're a good side and are full of winners, but when they lose they don't like it.
"They're bad losers and hopefully they'll be bad losers on Saturday."
But while Ferris is determined to get one over on the English at Twickenham this weekend he admits that his experiences on the 2009 Lions tour did give him a different perception on the 'enemy'.
"I went on the Lions tour and got to know a few of England's players," added Ferris.
"England are a good side at the moment and are very hard to break down. Saturday will be two good teams going against each other, but we're also looking forward to getting that result."
Ireland have won seven of the last eight meetings between the two teams, including last year's 6 Nations clash in Dublin when they denied England a Grand Slam at the final hurdle.
England's impressive victory over France in Paris last weekend means they still have an outside chance of winning the Championship but Ireland will travel in confident mood having returned from London with a win on three of their last four visits.