Farrell was speaking ahead of Thursday's Six Nations Opener against France in Paris.
Ireland head coach Andy Farrell says Jack Crowley will offer versatility off the bench in tomorrow's Six Nations opener against France.
The Munster out-half is among the replacements, with Sam Prendergast given the nod to wear the number ten shirt.
Farrell says he made the call based on what is required for the challenge posed by the hosts in Paris.

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