Ireland need a fully fit Johnny Sexton if they are to challenge for the Rugby World Cup, according to Brian O'Driscoll.
Sexton has not played for Leinster in 2019, sitting out the win over Ulster in the European Champions Cup quarter-finals due to a quad problem.
The 33-year-old fly-half was able to feature for his country in each of their Six Nations matches, but suffered a concussion against Scotland.
And retired Ireland great O'Driscoll is concerned about the key man's tendency to put his body on the line.
"I think of course there's a worry," O'Driscoll told the Daily Mail.
"You want your best player, or one of your best players, on the park whenever you can.
"He definitely got targeted against Scotland and I felt as though all of the collisions were right on the line. But I think it would've been hard to penalise any of those shots.
"That's the way that Johnny plays the game. Of course you would worry a small bit about the aggressive nature he takes the ball with but that's his selflessness in creating space for others out wide.
"There's a contingency with Joey Carbery in there, trying to give game time to the likes of Jack Carty as well, but if Ireland are to win the World Cup you do sense that they need Johnny Sexton."
