On Saturday afternoon Wales will enjoy, if that is the word, their second successive trip to a Rugby World Cup quarter final, when they come up against South Africa at Twickenham. As it stands, the bookmakers have the Springboks as fairly comfortable favourites and the court of public opinion seems to agree that the walking wounded Welsh team are underdogs.

For former Welsh international Gareth Thomas, this is a strong position for Warren Gatland’s side to hold, going into the quarter final.

“As far as underdog or favourite goes, we would take the former and be very happy with it. I don’t think South Africa are going to feel any more confident having been named favourites. I think Wales probably are the underdogs, which I like because Wales always perform better as underdogs.

“I don’t agree with people saying Wales could ‘surprise’ South Africa, because I think South Africa will be very aware of what Wales have to offer. When you look at the last year or so Wales have beaten South Africa [12-6 in Cardiff last November], and they pushed them very close in South Africa as well [30-31 in Nelspruit]. Ultimately these are two very close teams who play with similar styles, who both like to bring a lot of physicality. I am expecting an amazing, and closely fought, test match.”

Thomas knows better than most what it takes to prepare for World Cup knockout rugby; the winger accrued a modest 100 caps and 40 tries for Wales and played in four World Cups, including two quarter finals. Having retired in 2007 he is currently a pundit for ITV, and under this guise he told me what he made of Wales’ tumultuous pool stage.

“Put simply, they’ve done incredibly well to get here. After all the injuries and after being written off by a lot of people, the sheer team spirit they’ve shown has been outstanding. It was no matter of luck that they’ve ended up qualifying from their group, it’s a product of hard work and self-belief and through these things they’ve made the country of Wales extremely proud.

“They came in having lost two of their key players and yet the team hasn’t missed a beat. That’s not to say they’ve been perfect but everyone on the team decided to stand up; Dan Biggar has taken the responsibility of kicking and Gareth Davies has come in at scrum-half and put in one of the standout performances of the tournament. So players took their chances but throughout it all, there has been a team ethic and team value that has made Wales a very difficult side to beat.”

Part of what has made Wales’ survival in the tournament’s ‘Pool of Death’ so remarkable is the support and faith that Wales and Warren Gatland have received from their countrymen and the wider rugby public. With England, France and upcoming opponents South Africa having received hostile receptions on the home front, Thomas credits the coach and the players for staying on the same page despite an injury list longer than Luke Charteris’ arm.

“I think it’s a very difficult environment to create in a squad, especially when the easy option is to use the injuries as an excuse, and to accept that ‘people won’t be too angry if we lose because we were up against it’. They’ve shown tremendous self-belief to have the attitude that they can beat England and they can beat Australia, and it’s not just individual players, it’s a strength of character running through the whole squad. It’s an impressive thing to have built.”

Wales’ struggles with injury have been well-documented with Leigh Halfpenny, Rhys Webb and Jonathan Davies headlining the list that now includes Scott Williams, Hallam Amos, Cory Allen and Liam Williams. Even the backline injury cover in the form of Eli Walker is struggling with his own hamstring injury that initially saw him dropped from the squad, and with Wales’ back division severely depleted surely there has never been a better time for a shock comeback from the man they call Alfie?

“Oh, I can’t even get out of bed in the morning! I can’t bend down to tie my boots anymore! My body is paying the price for me doing my time in rugby and I have huge admiration for these players because I probably couldn’t play now. Actually there’s no ‘probably’ about it, I definitely couldn’t play to anywhere near the level of intensity that the game is played at nowadays.

“People ask whether I miss the game and I say ‘no’ because I enjoy watching the game and seeing what these players are able to do, and what they’re willing to put on the line to represent their country. I’m way too old and too unfit now; what I thought was a really tough game when I played, these modern guys would think it was a walk in the park!”

When pressed on what two teams he thought would face off in the final, you can see that the evolution from Gareth Thomas the player to Gareth Thomas the pundit is nearly complete.

“Ask me again on Monday! As far as this final eight goes, I believe that any of the teams still involved have the ability to win the whole thing, which is brilliant to see! Performance-wise I think Australia has been the side that have looked most commanding, but we haven’t seen New Zealand come out of the starting blocks yet.

“Not many of the teams have showed real consistency so this weekend is going to show who is capable of performing to the best of their ability, and who can only do enough. It’s been an interesting group stage and I think it has left everyone wanting more. This weekend is where teams have to come out and put their cards on the table.”

By Fraser Kay (@fraserkay)

Gareth Thomas features in the Guinness campaign which celebrates stories of integrity and character from the world of rugby. To watch the films visit www.YouTube.com/GuinnessEurope