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MARSEILLE - The changing physical nature of rugby union will never be more evident than in the World Cup, with teams relying more on power and pace to win matches than skill and flair.
Wales winger Shane Williams, standing 5ft 7in and weighing 13 stones, is an anomaly amongst the giants lining up in most international teams' backlines as the importance of physical dominance takes centre stage.
Williams, a master of the sidestep who caused England and New Zealand trouble when the sides met in the last World Cup, acknowledges that the game has moved on.
"The players are getting so big and so physical, and they probably believe they can run through players and defences," he told the Western Mail newspaper.
"But defences are much stronger and the collisions are amazing when you see them on the field.
"Seeing the likes of (France No 8) Sebastien Chabal run with the ball or hit somebody, well, it is just carnage."
He added: "I have trained my body for the hits. When I get hit by the 20-stone boys it's a massive collision for me. You get used to it and you shake the big hits off."
The advent of professionalism in 1995 revolutionised rugby. Players became stronger and speedier, with technical skills rising along with a much superior physicality on the pitch.
Players started to train more and importantly train scientifically, benefitting from nutritional advice and the support of a raft of specialised backroom staff.
For club owners came the importance of securing the win, often at the detriment of free-flowing rugby.
Teams now play with intricate defensive patterns, often drawn up by former rugby league coaches, that have transformed games into contests of attrition.
Ex-Wigan and Great Britain league legend Shaun Edwards coached Wasps to European Cup victory last season on the back of his infamous "blitz defence".
On the other hand, attack coaches are hired in a bid to break down these tightened-up defences, the emphasis placed stoically on the making of hard yards and pouncing to capitalise on a rival team's errors.
To compare the rugby World Cup of 1987 to the 2007 edition would be nonsensical.
One player who appeared 20 years ago was Scotland's Gavin Hastings, but he argues that the workings of his position of full-back have been completely overhauled since his day.
"Traditionally the full-back has always been the last line of defence," he told BBC Sport.
"But for me the position has changed dramatically since the professional era took over.
"Defences are so well organised now, the full-back is hardly required in first phase play in defence.
"And the full-back and two wingers are far more in collaboration and more capable of interchanging than they did when I played."
Ground-breaking former All Black No 8 Zinzan Brooke, who displayed the running and kicking skills of a back and famously kicked a 47-metre drop goal during a 1995 World Cup match against England, also highlighted the vastly different requirements of backrow forwards nowadays.
Speaking about the role of the openside flanker, Brooke said: "It's such an important role now, and that's one area of the game that has changed so much since my playing days.
"Because defensive lines are so tight in the modern game, the open-side's role is turning rucks and mauls into play again."
Statistics back up Brooke's prognosis. Fewer tries are scored by sides that hang on to phase-after-phase of possession compared to the large majority scored from turnover ball and blistering counter-attack - the speciality of this year's hot favourites the All Blacks.
One inescapable fact about rugby union is that, at this top international level, it is a very physically demanding, and sometime brutal, game that results in a high turnover of injuries.
JPR Williams, the fearless former Wales and British Lions full-back and orthopaedic surgeon, was in no doubt over the reason for the increasing injury lists.
"You have only got to look at the number of injuries to see that producing bigger, stronger players is resulting in problems. There is no doubt the increased physicality of the game is the cause," Williams argued in an online debate in The Guardian newspaper.
"You have to ask how much longer the players can continue to meet what is asked of them.
"I believe that if things continue as they are you will see stars who could have reached the highest level blown out in only a few years. My concern is whether rugby union can be sustained in the professional era."
- AFP