Keith Wood believes France could try to expose one potential weak spot in Ireland's defence in the second Six Nations match.

The former Ireland captain was previewing the game on Off The Ball tonight and pointed out an area of concern in the outside channel around the 13.

"If [Ireland] are challenged in a straight line or cutting line, I'd have no issue with them whatsoever. I think they'll stand up to the challenge. They might get knocked over a couple of times and somebody else will have to cover for them. But I don't have a worry for them in that instance," said Keith.

"The issue is when they get exposed on the outside of Jared Payne - that outside channel. There's a bit of a nether region there that a French backline in particular - if they do decide to have a bit of depth and cause a bit of carnage - can test the guy who isn't entirely certain whether he comes up or in, to do what Brian O'Driscoll did so very well and read that situation perfectly. Jared Payne hasn't had the time to figure that out yet." 

Keith said he had spoken to Jonny Sexton today and the No 10 told him that he will feel the pain after so long on the sidelines.

"I had a chat with Jonny Sexton today and he's in no doubt that physically it'll hurt and that he has to get to the pace and pitch of the game as fast as he can," he said.