Marshall joined Jason Mohammad in the Sport Wales studio

With the Rugby World Cup about to kick off, former All Black scrum-half Justin Marshall has branded Wales a team of underachievers.

Speaking on new BBC Wales show "Sport Wales", Marshall says he understands why the Welsh public feels frustrated.

The Ospreys star says that when you look as the sum of its parts the Welsh team should be doing better.

He goes on to say that favourites New Zealand have "only" a 90% chance of winning the World Cup.

SPORT WALES DEBATE ON 606 Justin talks candidly about life as an All Black and as an Osprey Jason Mohammad

Marshall, who is the second most capped All Black player of all time, says that Wales should have done much better in their World Cup warm-up games.

"I know that this is going to hurt, but I feel Wales are underachieving, definitely underachieving," said Marshall.

"It must be frustrating for the people of Wales because if you look at the make-up of the team - and the players that they have - they should be doing better.

I would say that the All Blacks have a 90% chance of winning, the other 10% is sport Justin Marshall

"The results should be a lot better than they have been."

But he does understand the pressure the team are under.

"I don't want to be critical - and I'm not going to be at this stage because it's the wrong time for it. I'm a rugby players and I know what the pressures are like," he said.

"There are some things that are wrong and need to be put right, but it's too late now."

Marshall, who has played in two World Cups, says Wales must now focus on doing well in the group games.

"What they have to do is to get some confidence from their pool and if they can crack Australia at the Millennium Stadium that would be fantastic," he said.

When it comes to the chances of his fellow countrymen, Marshall says that the All Blacks must be favourites to lift the Cup.

606: DEBATE Jason Mohammad on 606

"From what I have seen in the last three and four years there are only four teams who could win it.

"Favourites New Zealand have had the best preparation, Australia are always a danger, France with the home advantage, and outsiders South Africa.

"I would say that the All Blacks have a 90% chance of winning, the other 10% is sport. What I mean by that is on any day any team could win.

"Having been in a side that has lost to the underdogs on two occasions I know what that is all about!