Joe Schmidt says Andrew Trimble's lack of recent game time led to him taking the "very, very difficult decision" to leave the Ulster wing out of Ireland's World Cup squad.
The 30-year-old winger's absence from Ireland's 31-man squad was the main talking point and Schmidt said it had been a "very difficult decision".
"We spent six hours on Sunday (picking the squad)," said the Ireland coach.
"For some of those six hours Andrew was coming to the World Cup. That's how tight it was."
The Ireland coach added that his team's "manufactured midfield" had led to the decision to include specialist Ulster centre Darren Cave in the 31-man squad.
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