Former Ireland head coach Eddie O'Sullivan says Canada have been at a low ebb as Ireland prepare to take them on in Saturday's Rugby World Cup opener.

O'Sullivan faced Canada on numerous occasions while USA head coach between 2009 and 2011, and he believes Ireland can run up a big score if they take advantage of their opponents' brittle confidence.

"Canada have always been a dangerous team to play and their history with the US has been that they've been the stronger team traditionally when it comes to the US. They have strong rugby programmes in their country - albeit similar to the US and they've always managed to deliver when on the big stage. But this Canadian team has been through a dreadful summer, surprisingly so," he told Newstalk Sport today.

"They've really had  string of losses which is not very Canadian in the way they play the game. So I would worry for Canada at the moment. It's not your traditional Canadian team, who basically are capable of scaring anybody on any given day. I think at the moment, this Canadian team will be very low on confidence."

"They are getting a couple of players back. That will certainly boost them - Jamie Cudmore in particular, who has been missing all summer. But I think this Canadian team is very brittle and if Ireland can get in front of them early in the game, it could be a rout. Canada are tough but I've never seen a Canadian team in such a brittle state. So I think it's up to Ireland. If Ireland deliver big performances, there's no chance for Canada to do anything in this game."

Tomorrow on Newstalk Sport, Eddie will tell us what it is like to coach a smaller rugby nation like the USA at a World Cup.