"I have a lot of admiration for Sexton", 36 years old and 102 selections with the green jersey.
"He's a model of longevity, he's the emblem of this team, he's their captain," said the French N.10, who is only 22 years old and has "only" 24 selections.
"He's one of the best openers in the history of international rugby. Despite his age, he's still incredible, he still makes great matches every weekend," added the Stade Toulousain flyhalf. .
Sexton is "an incredible weapon" for the Irish, who won Wales 29-7 on Saturday (including 9 points from their opener).
“He is one of their key players so we will have to watch him and put a lot of pressure on him”.
Ntamack believes that the Irish will be the "favorites" of the match on Saturday (5:45 p.m.) at the Stade de France, a kind of small "final" before the hour between the two leaders in the standings (5 points), on behalf of the 2nd day of the Tournament.
"I don't think we are favourites, (on the other hand) the Irish fully deserve this status because they have demonstrated it for a number of matches," he said.
"They've been unbeaten for nine games, they had a huge November tour (3 wins in 3 games, including one against the All Blacks, editor's note), they just had a great game against the Welsh... So no, I don't think we're the favourites, we'll leave them that status," he said.
For Ntamack, the Irish "well deserve their third place in the world rankings", according to the latest score from World Rugby published on Monday.
© 2022 AFP