10 Dec, 12:23
Ireland's John Lacey will referee his first ever RBS 6 Nations match in February, while Alain Rolland is also included in the Elite Panel in what is his last season.
"It's a big boost to have Peter back for a game like this. It's a pivotal game in the Six Nations for us and this is the one you want to have a full deck for. If we win we're right back in the hunt again," explained O'Sullivan.
"Peter is probably the best passer of the ball in the world at number 9. He gives the receiver so much time. The odd one goes astray but when you pass the ball 60 or 70 times in a game there's going to be one or two off target.
"He has a capacity as well to get us out of jail. He's done that a couple of times in big games where there's been massive line breaks when you could see nothing but a try coming, and he comes out of nowhere and takes somebody down with a hand trip.
"It's not the dog in the fight, it's the fight in the dog with Peter. He does box well above his weight all the time. He puts in a huge number of tackles and always tackles people that are bigger than him because there's nobody smaller than him on the pitch."
Despite his size, Stringer cuts an authoritative figure behind the Irish scrum and his presence and experience - tomorrow will mark his 74th cap - will be vital in the so-called 'championship minutes' against England.
O'Sullivan added: "He's a good organiser, he barks at the pack and keeps them in line and they're all afraid to cross him and that dynamic is very important in a pivotal position.
"Isaac Boss had a fine game the last day but Peter has that extra edge of experience and he knows most of the pack that bit better than Isaac, having played with Munster.
"There's a little bit of pressure on Peter because he knows he has to put in a big game after being out of commission for a few weeks, but he is one guy I wouldn't worry about under pressure. He tends to get on with his job and the bigger the game the harder he works.
"That's why it's good to have him back. It's a good settling influence in that area of the field for us I think."