The Irish stuttered to a 9-6 lead in the first half against Italy but were much improved after the break as they secured a 36-6 win.
Next up is a quarter-final against Wales with a semi-final against the winners of the France-England tie at stake.
"It's going to be another great challenge," Ireland captain O'Driscoll told ITV.
"It's been very close in recent years and it'll be the team that turns up on the day that goes into the semi-finals."
Defeat to Italy would have eliminated the Irish, he added: "We're delighted with the win.
"We knew we needed it and I'm glad we were able to deliver in the second half aided by what has been the best crowd we've played in front of so far."
Gilbert has released a new line of rugby cleats. The Gilbert Virtuo 8S is part of the exciting new product. Check it out.
The entire All Blacks apparel line has been updated for 2013/14. Check out the New Zealand All Blacks polo.
The Nike Tiempo is a solid rugby cleat and one of few styles still made from full-grain natural leather.
The Gilbert Blitz 8S rugby cleat is a great cleat at a great price of $69.99. Get a new pair of cleats today.
A cool looking all black rugby cleat with the high performance adidas is known for. Get in the Gear!
Wear the crest of the British and Irish Lions on your t-shirt. A great look for the summer.
$29.99
The All Blacks Performance t-shirt is black with hints of blue from the training jersey. Very Cool.
The New Zealand All Blacks training jersey for 2013/14. Get in the Gear!
The USA Rugby Pro Alternate rugby jersey is perfect for any fan of the Eagles. Get yours to wear during the summer Test matches.
The NEW All Blacks 2013/14 jersey has arrived at World Rugby Shop. Dare to wear the colors of the All Blacks.
