Jonathan Davies has dismissed as “ unthinkable” suggestions that the British & Irish Lions will tour South Africa without world player of the year Shane Williams.

The Wales and Ospreys wing has been at the centre of debate over the weekend concerning his perceived defensive weaknesses and will discover today if he has made the 35-man party that will be announced for the 10-match trip which starts at the end of next month.

Davies, who starred in both union and league, could be accused of Welsh bias, but is adamant that Williams is one of the few players available to the selectors with that “X factor” — the ability to conjure a try from nothing against a side who will be overwhelming favourites to win the three-Test series.

Davies said: “In my mind their is no debate about Shane and it's unthinkable for the Lions to take on the world champions without him being an attacking option in the squad. I simply don't understand why there is any talk about him, even when you discuss the defensive side of his game. Yes, I admit he hasn't had the same season as 2008 when he won the world player of the year, but that was an exceptional series of performances and he still remains a potent try scoring threat.

“He has to go and having been on the last Lions tour, he understands the kinds of pressure that you must deal with like homesickness and being out of your normal comfort zone.

“Once on the tour, the selectors can make the call about his form, but the hard grounds are going to suit his style of play and while there will be concerns about his defence in terms of dealing with the high kicks to the corners, you could have made the same argument about not picking Jason Robinson for England or the Lions.

Jason was selected because of his attacking threat and that's the case with Shane.

“We are not going to be able to dominate the Springbok forwards and the best line out in the world and our back row will not be able to compete with their unit in the close quarter-stuff and so we need guys like David Wallace and Martyn Williams to be flying around, snapping up loose ball and allow Shane and the other backs to counter attack.”

Davies believes the Lions coaching team — headed by Ian McGeechan, the London Wasps director of rugby — gives them a real edge, one that could counter the physical threat posed by a Springbok squad only too aware of the Lions Test series triumph on South African soil in 1997.

He said: “It all comes down to devising the right strategy and the Lions have a group of very experienced and clever coaches headed by McGeechan and this is one area where we are better than the South Africans. At the moment, we have the edge and if we need to think outside the box as the tour unfolds then men like Shaun Edwards, Rob Howley and Warren Gatland will be able to come up with counter measures.

“That group of coaches ticks all the relevant boxes and while we are underdogs I am happy with that situation because all the pressure and expectation of an entire nation is on the Springboks. They will have to deal with that every day of the tour.”

With Gavin Henson ruled out by injury and Danny Cipriani unlikely to make the tour, there are concerns that the Lions will lack the individuals to bring something different to the tactical plan. Davies admits this could be a worry, but he sees men like Lee Byrne and Williams providing the necessary inspiration.

He also expects Brian O'Driscoll to prove that he is still a world-class player and to be a certainty for the Tests. O'Driscoll had been touted as a captain for the tour but he has lost out to Ireland team-mate Paul O'Connell, whose appointment will be confirmed today.

Despite a glittering career Davies never represented the Lions as his decision to join the league ranks meant he missed the 1989 trip to Australia and he wasn't in the frame for the 1993 tour to New Zealand.

However, touring with the Great Britain rugby league side put Davies in a similar “them against us” situation as he took on the Australians on their home soil and he admitted: “I do regret not making a Lions tour because I believe the whole concept is fantastic.”

* Jonathan Davies is an ambassador for Rugby Expo 09, The Business World of Rugby, which is at Earls Court on 24-25 November. For more details visit: www.rugbyexpo.com