New dimension dictates that big is beautiful rugby union: Players' ever-growing build confirms that size counts in the moder n game. Steve Bale reports

RUGBY UNION : Jack Rowell has left the door ajar for Neil Back but if Back were to reflect on it he would surely have a go at hooker. In the England squad he is surrounded by huge men and the Rugby Football Union has said it wants them even bigge r - at hooker, at any rate.

It is the rugby age we live in that accords primacy to size, and you need only look at the back five in the England pack who will face the Irish in Dublin on Saturday to see the point. The average height of the eight is 6ft 3in, but of the second and back rows it is a neck-cricking 6ft 61/2 in.

Purportedly Back's 5ft 10in is, as Geoff Cooke made brutally clear during the pre-Rowell managerial regime, not up to the modern flanker's mark - though, if this really is the case, then we can abandon the quaint notion that rugby is a game for all shapes and sizes. All sizes maybe, if you include the backs, but at international level the days of the Toby Jug prop are past.

There was a time when the relatively lightweight Back would have begged to differ. "For the game I play my size is a massive advantage in that a bigger guy would have to be extremely agile to get up and down and make all the tackles that I get through during a game," he used to say.

When Cooke remained unpersuaded Back somehow undermined his own argument by setting out to add 10lb to his 13st. "I'm changing my focus with the intention of keeping my strengths - speed and mobility - and building up my strength and power," he said. He subsequently won two caps but has now returned to the fringe, the A team who play Ireland A tomorrow.

In fairness to Back, Rowell is not quite sure what he wants in his back row and is not yet convinced that he can do without a proper, fast-moving, free-ranging open-side such as Back on the hard grounds of South Africa during the World Cup.

But at the same time the movement towards sheer size, meaning weight as well as height, in the English game and elsewhere seems inexorable, so much so that Gareth Adams, a similar but slightly larger flanker who captained England Under-21 from that position, has turned into a hooker this season.

"There is no doubt about it, as you can see from our combinations, particularly in the back row, that size is an important factor and we have endless debates about smallness and effectiveness against largeness and effectiveness," Don Rutherford, the RFU'

s technical director, said.

"At international level there has clearly been a significant change over the years and we have to confess that we have been trying to find larger hookers, because we find our major competitors have larger hookers who are also very good players."

Rutherford - a compact 5ft 81/2 in - was England's full-back 17 times from 1960 to '67. "When I came into the team Marques and Currie were the second row. Richard Marques was 6ft 5in and I thought he was a very big man. Since then, it's fair to say everyone has got bigger, so you would expect rugby players to have got bigger as well."

And how. If you go back to England's double Grand Slam team of 1923 and '24, the tallest forward was Tommy Voyce at 6ft 1in and the heaviest Wavell Wakefield at 14st. Seventy-one years on, Martin Bayfield is 9in taller than Voyce and 5st heavier than Wakefield.

Before that, forwards were shorter still; indeed until Wakefield came along, nowhere had forward play ever been broken down to its constituent parts. So there was no such thing as a line-out specialist and players used to pack down in the order they arrived at a scrummage.

Even up to the late Fifties teams got by with relatively small men. The French who famously won the 1958 series in South Africa had one player - Bernard Mommejat - standing 6ft 3in but no one else of more than 6ft 1in. Alfred Roques, who was esteemed as one of the most rugged props the game had known, weighed just 12st, 4st less than his present England equivalent, Victor Ubogu.

Self-evidently it is not merely bulk but how you use it that matters. If Ben Clarke and Tim Rodber, for instance, were ineffective players it would not matter what their dimensions were. Accordingly, though Brian Moore, the England hooker, is 5ft 9in and14st 9lbs - 3in and 21/2 st less than Phil Kearns of Australia - he is about to win his 55th cap.

"There is nothing wrong with trying to find players of size and physique but what I would also say is that you can't pick people on the strength of their physical make-up unless they are good enough," he said. "It depends totally on the ability of the player."

Moore was faced by the heaviest hooker of them all, Australia's 181/2 st Tom Lawton, in the Lions series of 1989. "At first look, it seems quite obvious that a good big 'un will beat a good little 'un but it's not," he said.

"When I played against Lawton I was giving away 4st but in the deciding Test in Sydney one of the key moments was when we pushed them off the ball at a scrum on our line. It was a crucial strike, that, and rather proves my point."

Even so, the point is rather lost on Rutherford. There was a Scotland lock of the Sixties called Peter Stagg who, because he was 6ft 10in, was regarded as freakish. Now Wales have their own 6ft 10er in Derwyn Jones. And even after Bayfield, England have the 6ft 9in Simon Shaw waiting for his chance and, in descending order, Martin Johnson is 6ft 7in, Rodber 6ft 6in, Clarke 6ft 5in and Dean Richards, who is a miniscule 6ft 4in.

What is more, they are only the top of the pyramid. "The great thing about the large number of great big men in English rugby is not just their extreme size but that they are athletic with it," Rutherford said.

"There was a time when we would have looked at these guys as unusual but now, provided the individual has the necessary drive and aptitude, anything is possible."