The best sports teams constantly look to reinvent themselves. Their core principles remain in place but, crucially, they never, ever stand still. To do so is to risk slipping backwards relative to their competitors and arrive at the worst of all possible outcomes: a poorer, less successful version of themselves.The ultimate example in rugby, until now, has probably been the All Blacks. For decades it was not only about winning the next game, but underlining their position, to quote one of their motivational whiteboard slogans from 2013, as “the most dominant team in the history of the world”. When you are chasing that kind of rarefied target, you don’t allow the grass to grow beneath your jandals.Even the greatest All Black sides, however, never won three consecutive Rugby World Cups. Something or someone would always get in the way, whether it be a mystery South African waitress or a temporarily inspired bunch of Frenchmen. New Zealand did lift the Webb Ellis trophy in 2011 and 2015, but an unprecedented treble has remained stubbornly elusive.Which now leaves the door ajar for their long-time rivals South Africa, champions in Japan in 2019 and in France in 2023. To be inside a fervid Ellis Park, their traditional citadel, last Saturday and witness their 45-21 win over England was instructive on several fronts, but there was one entirely unavoidable takeaway. Is there anyone out there with the physical firepower to stop the Springboks when the world’s leading sides converge on Australia next year?England were gallant, but anyone would have struggled to contain the hosts when they were in full flow. “They’re just very good when they get into that cycle,” said Jamie George, England’s captain. That was despite the Boks being without, among others, Siya Kolisi, Eben Etzebeth, Lood de Jager, RG Snyman, Franco Mostert, Wilco Louw and Sacha Feinberg-Mngomezulu. A new green machine with go-faster stripes is emerging from Rassie Erasmus’s workshop and it spells potential trouble for all and sundry.South Africa's Grant Williams and Damian Willemse celebrate winning the match against England. Photograph: Steve Haag Sports/Darren Stewart/Inpho [ South Africa make a statement with Nations Championship rout against EnglandOpens in new window ]We are certainly going to see plenty more of Zach Porthen, Cameron Hanekom and Paul de Villiers in the years ahead. Even if one or two old reliables dip over the hill in the next couple of years, Erasmus already looks to have pulled off the cutest of tricks. Blood talented youngsters, encourage them to stake a permanent claim and then watch their seniors respond accordingly. Get that balance right and there is no surer way to regenerate the collective.The same applies to those who have already been around the squad for a while. Damian Willemse, Grant Williams, Canan Moodie ... their ability has never been in doubt and experience is improving them further. Which puts the onus on everyone else to try to catch them up. New Zealand and France, as demonstrated by last Saturday’s excellent game in Christchurch, are the likeliest candidates and both camps will have been cautiously encouraged by their initial Nations Championship outing.The All Blacks have started to play proactive All Black-style rugby again under Dave Rennie and look much happier for it. France, without numerous frontliners, scored four tries and gave notice of their own impressive depth. On another day, Matthieu Jalibert might easily have conjured another score or two and their missing Toulouse aristocrats will be back this autumn to complicate life further for their opponents.It will also be interesting to see what unfolds when Ireland pitch up in Auckland on July 18th. The All Blacks’ unbeaten sequence at Eden Park stretches back 52 Tests to 1994, but old certainties are under increasing strain. There was an average of 63 points per game on the opening week of the Nations Championship and sides unable to rack up in the region of 30 points will find it hard to win games regardless of the opposition or the venue.Ireland’s Stuart McCloskey celebrates after beating Australia. Photograph: David Neilson/