England ruined Ireland's designs on consecutive Grand Slams with a brutal 32-20 victory over Joe Schmidt's men in Dublin, while Wales conjured a stirring comeback to sink France in Paris.
Here, Press Association Sport runs the rule over the opening weekend of the 2019 Guinness Six Nations.
England's triumvirate of power bullies the stunned Irish
Manu Tuilagi's first Six Nations start since 2013 transformed England. The Leicester juggernaut bludgeoned through Ireland's midfield right from the off, with the undercooked hosts finding no answer whatsoever. Throw in fit-again Vunipola brothers Mako and Billy, and England had three dump truck power mongers that Ireland simply could not stop. Keep all three fit, and England can seriously start to plot the route to glory at World Cup 2019.
Slade comes of Test-match age
Exeter Chiefs centre Henry Slade has long since boasted all the raw materials for Test-match success. A physical edge to add to plenty of finesse, the rangy midfielder knows how to unlock defences. And England boss Eddie Jones admitted in the wake of this two-try showing that the 25-year-old has finally realised just how good he can be. England may well have stumbled upon their World Cup midfield, thanks to an injury to Ben Te'o, because Slade's partnership with Tuilagi and his links with Jonny May caused Ireland untold troubles.
Record comeback win puts Wales on title tilt
Warren Gatland's last Six Nations as Wales boss so nearly started with a whimper. But then France imploded. Wales trailed 16-0 at one stage, but edged home 24-19 as Les Bleus slipped woefully off the pace. Wales will not care how they won, simply that they did. Gatland's teams tend to grow into every Test window too. If they really find their rhythm, they could easily contest the title now.
Ireland hit with World Cup "reality check"
England's potency left Ireland's hopes of becoming the world's top Test team in tatters. Anyone with any sense of nuance knew full well that New Zealand boss Steve Hansen was cranking up the mind games when he installed Ireland as the best team in the world in November. Ireland's stunning 16-9 victory over the back-to-back world champion All Blacks in Dublin still merits huge respect, even in the wake of their Six Nations thumping by England. But New Zealand are still the team to beat. England are right up on the rails though, leaving Joe Schmidt with precious little to say except that the manner of Ireland's Dublin loss carries worrying World Cup portent.
Italy no closer to bridging the gap
Former Harlequins coach Conor O'Shea has done a sterling job in building Italian rugby's infrastructure behind the scenes. But the ex-Ireland full-back is also head coach of the Test team, and despite three late tries to gloss the score against Scotland, this was another below-par start from the tournament's regular strugglers. Scotland's 33-20 victory reads far better on paper than in the flesh. The Azzurri have plenty of work still ahead to catch the Six Nations' main pack.