The midfielder was stretchered off in the 2-1 loss to West Brom on Saturday afternoon, with fears that he could be set for an extended spell on the sidelines.
It has since been discovered that he has picked up a knee ligament injury according to BBC Sport, with his set to be out for around three months.
His absence will be sorely missed over the busy Christmas period, and Carragher says he thinks it’s a big blow to the side and predicts that it will affect them massively this season.
“It’s a big blow,” he told Sky Sports.
“We spoke for years about Arsenal and a holding midfield player, and fortunately for Arsene Wenger he found one from within. He’s become vital, to miss him now, I think it’s going to affect them massively.”
The former defender also says that back up duo Mikel Arteta and Mathieu Flamini are not good enough to replace the Frenchman in the side.
Coquelin has brought a strong defensive nous to the team since his introduction, with his competitive nature helping their attacking players to flourish.
His constant running has also been a big bonus for them, but backups Arteta and Flamini have failed to replicate that when brought in to the team.
And Carragher has questioned why they didn’t move for Morgan Schneiderlin in the summer.
“Schneiderlin was the player that most suited Arsenal,” he added.
“Flamini and Arteta are not enough for Arsenal Football Club to get where they want to be. They needed to make a big signing in there.”