Brian O'Driscoll believes Ireland face "trouble" if Jonny Sexton faces any injury problems in future.
The Ireland legend was guest presenting Off The Ball tonight as always on a Friday, and when Joe Molloy asked him if Ireland risked being half the team in the absence of his former Leinster colleague, Brian responded: "I do think it's trouble. With the greatest of respect to Ian Keatley and Ian Madigan, they're both very fine players. But they're not Jonny Sexton. Jonny Sexton definitely is the best 10 in the world at the moment and he's probably the best player in the world at the moment."
Meanwhile, the plaudits have been raining in on Ireland's Conor Murray and Brian had another big one for his former team-mate.
"He's excellent, he's a top quality player. Whatever about him being the best 9 in the world - maybe he's in the shake up - he's definitely the best defensive 9 in the world. That's going back for years. he was always a good defender," said Brian.
Conor Murray and Brian O'Driscoll on the last Lions tour ©INPHO/Billy Stickland
He also gave his take on Ireland's victory over England last Sunday and was impressed by how comfortable Joe Schmidt's side looked with kicking and the game-plan.
He also gave an insight into the way work on the training ground have made Ireland even more formidable, especially in the pack's brilliance in the ruck and breakdown.
He also had an interesting point on being a good defender in rugby.
"You can be a good defender and a bad tackler, or the other way round. They don't always go hand in hand. [Ex-England] Mike Tindall was excellent at both, at reading situations well but also going through and the actual act of tackling. And your tackle isn't finished when you hit someone to the ground," said Brian.
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