England shouldn't get carried away, even when tempted to take flight on the wings of euphoria. And here is Martin Johnson to give a hand, answering a question earlier this week on whether he could name the precise date on which England closed the gap with the rugby giants of the Southern Hemisphere.

"When I came into international rugby in 1993," the England captain said, his brow darkening, "we beat New Zealand twice in my first year, with England and the Lions. But we've never beaten them since. So that knocks that one on its head, really."

This kind of engine-room realpolitik is what a coach needs to hear from his players, and particularly from his captain, when the team are on the eve of a rendezvous with the Springboks, whom they meet at Twickenham today. In no sport more than rugby, for some reason, does hubris so regularly receive its brutal comeuppance.

And England, given their hat-trick of last-minute grand slam failures in the last three years, are probably more aware than any other team of the danger of taking their own recent form as a guide to anything at all.

Nevertheless, many people are saying that, as they enter the fifth year of Clive Woodward's reign as manager, England have indeed closed that famous gap and are now consistently operating at the same level as the southern triumvirate. Jack Rowell, Woodward's predecessor, is a firm believer. So is Pierre Villepreux, the technical director of the French rugby federation and one of the European game's great tactical visionaries. And Woodward, not a man to boast, even said it himself this week.

"I don't think there is a gap," he remarked. "In fact, I don't think there's been a gap for a long time. Of course, it's difficult to judge when we're playing these sides out of season. But, anyway, I'm not paid on gaps. I'm paid to win rugby matches."

If the gap has indeed disappeared, then perhaps the signal of its closure can be dated to the Saturday afternoon at Twickenham almost exactly three years ago when Woodward's team met Nick Mallett's Springboks. Riding high on a run of 17 consecutive victories, Mallett's team looked as good as invincible. England took them on, established their superiority in every phase of the game, and registered an unusually satisfying 13-7 win.

For Woodward, it was a first taste of victory over one of the Tri-Nations teams in his new capacity. He had begun his reign by drawing 15-15 with Australia at Twickenham, followed by a run of seven defeats and one further draw before the arrival of Mallett's team. Since then, England and South Africa have met four times and registered two victories apiece, which certainly suggests the establishment of competitive parity.

Woodward's overall record against Australia, New Zealand and South Africa includes five wins, two draws and 11 defeats. But the balance of the results has been undergoing a radical change, and all of their last four matches - two against the Wallabies and two against the Springboks - have resulted in victories.

Only New Zealand, whom England have not faced since the defeat by 30-16 at Twickenham in October 1999, remain to be added to his list of conquests.

The All Blacks are currently in a rebuilding phase, but New Zealand rugby remains the reference point in the minds of players of Johnson's generation. "I played in New Zealand when I was 19, 20," the 31-year-old captain said, "and they took the game seriously long before we did in England. Way back then the preparation was a lot more professional and it's taken a while to catch up.

It's not just about the top team. You've got to have players coming through who're playing a good competitive level of rugby from their schooldays upwards. Now we've got young guys who can come in and play Test matches and not look out of place and play very well. It's taken a big shift of culture to get there but I think we're getting close."

According to Villepreux, there are two reasons for the success of the England team. "First, the England players now offer the same physical potential as the Southern Hemisphere teams," he said yesterday.

"But that's not the main thing. More important is that they've completely changed the way they play rugby. The Woodward method makes them free to run with the ball and play with a lot of flair. Kicking is still a part of the game, of course, but it's not the first message the players get from Woodward.

"It's to be used when necessary, as a secondary option. And, evidently, England have produced a lot of talented young players - not just that but players who can play together, which to me is very important."

In the view of Rowell, England's manager from 1994 to 1997, the arrival of a generation of gifted and mature young players is the direct result of the higher quality of rugby to be found throughout Premiership clubs.

"Since professionalism settled down," he said yesterday, "we've all been on a level playing field. The Premiership is a fiercely competitive affair and the quality is improving by the month. The dynamics are similar to Premier League football; it's devil take the hindmost and the foreign players and coaches have helped to make it a world-class competition."

England's biggest asset, he said, is the size of its playing pool, and the big investments made by the owners have enabled more young men to envisage a career as a professional rugby player, thereby increasing the intensity of the competition for places in the international squad.

"If you've got a conveyor belt of talent in operation, you can sustain the level of internal competition. That's been a very important change."

On the tactical side, he said, all clubs now encourage their players to move the ball around, easing the individual's transition to the international squad, where the emphasis under Woodward and his assistants is on a high-tempo attacking style.

"In Jonny Wilkinson," he continued, "England have the outstanding number 10 they've needed since Rob Andrew retired. They have a battle-hardened pack who never take a step backwards and can match anyone for power, but they can play too. You'll often see England attacking with a back line that isn't made up of backs."

And, he added, they have Jason Robinson, whose inclusion at full back against Australia last month signalled Woodward's willingness to take risks in order to maintain the team's evolutionary momentum, and an ambition to lead the world in the game's tactical development.

"That's one of the key things," Johnson said. "We try to be innovators as well. I think Australia probably led the world in innovation in rugby the last couple of years, and before that it was probably the All Blacks.

"When I was growing up, the coaches always talked about the New Zealand teams in terms of excellence and innovation, never about England. We've got to try and change that. Throughout the '90s we tried to follow what the Southern Hemisphere were doing but since Clive's been here there's been the attitude that we've got to try and make improvements and try to get them to follow us." So far it seems to be working.