McNamara: O'Sullivan has been a huge bonus for U-20s
The Ireland U-20s will look to get a big weekend for Irish rugby off to an ideal start by winning their own Six Nations championship on Friday night, but they will have to do so without their influential hooker Ronan Kelleher.
The Leinster Academy player was forced off with a shoulder injury in last week's win over Scotland, and he is awaiting results of a scan.
England will provide stiff opposition for Ireland as they have their own sights set on being crowned champions.
Ireland must beat England and hope that Wales do the same to France without the French picking up a bonus point.
It's a tall order but one that is not beyond the realms of possibility, especially as Ireland's confidence is high.
Jack O'Sullivan has emerged as a star for Noel McNamara's side and the head coach has been impressed.
Filling the boots of the injured Caelan Doris wasn't easy, but O'Sullivan has been outstanding.
Doris is due to return for the World Cup in June, which will certainly give McNamara a welcome dilemma.
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"Listen, we would love to have that headache of trying to find a way of getting the two of them in together," he said.
"It is probably a testament to Jack O'Sullivan that nobody has mentioned Caelan Doris over the course of this championship.
"It is easy to forget Caelan was probably the best number eight in last year's championship.
"The biggest strength of the pathway here is that there are a lot of people working very hard at improving these players on a consistent basis.
"There's a great clip of Jack in JCT final for Pres, making a cover tackle in the corner on the Crescent winger off a scrum to win the game for them.
"He is a guy who has probably found his feet really well this year. He would have played Irish schools a year young and the second year wasn't involved.
"He is somebody who has been on the radar and who has done some really, really good things. The thing you've got to say now is consistency of performance is the biggest thing for him now. He has taken his opportunity. He has been a huge bonus for us."
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