Ireland derail England hopes
England collapsed to an alarming 19-9 defeat by Ireland as their pursuit of a first RBS 6 Nations title under Stuart Lancaster derailed spectacularly at the Aviva Stadium.
Jonathan Sexton inspired the reigning champions' 10th successive victory by producing a masterclass in game management, while his half-back partner Conor Murray also flourished behind an Irish pack that played with furious intent throughout.
The only surprise at half-time was that they led by just six points despite having been superior in every department, with Sexton directing operations with calm authority.
And the manner in which they ratcheted up the intensity in the third quarter was reminiscent of New Zealand, with Sexton's vision initiating a try for Robbie Henshaw that established a 19-3 lead.
Inside centre Henshaw was named man of the match, but that accolade could easily have gone to Sexton who decorated his display with four penalties and a conversion.
England were over-run for lengthy spells of the second half and apart from a characteristic fightback in the final quarter, there was little to applaud in a chastening afternoon.
They had been out-thought and out-muscled in a loss that has worrying implications for their hopes of mounting a meaningful challenge at the World Cup and reduced their stirring victory over Wales in Cardiff three weeks ago to a distant memory.
In contrast, Ireland have confirmed their position as the dominant force in European rugby and their coronation for a second year in succession surely awaits on March 21, with only Wales and Scotland capable of halting their march to a Grand Slam.
The reputation of their head coach Joe Schmidt continues to soar and the Kiwi will have savoured this result and performance, having stated before the game that the 13th win of his 16 matches at the helm would be his most treasured achievement.
Schmidt may have to plan for the final two rounds without his bulldozing openside Sean O'Brien, however, as the biggest match of the 2015 Six Nations inevitably witnessed a significant concussion incident.
O'Brien was struck when tackled by Billy Vunipola, rising to his feet before lurching back over on to the turf as if drunk. Once regaining composure with the team doctor in attendance, he departed to bring his afternoon to an end.
England had been braced for an early onslaught and the reigning champions did not disappoint, with two Sexton penalties nudging them into a 6-0 lead with only eight minutes on the clock.
Mere inches separated them from a try as they launched waves of attacks from a pair of five-metre scrums, but the visitors' defence was strong.
Luther Burrell carried hard as England bristled in response, finding reward in the form of a drop goal by George Ford, although the Bath fly-half then pulled a long-range penalty wide.
Wing Simon Zebo plucked a bomb from the air despite being surrounded by white shirts, but Ireland suffered a setback with O'Brien's removal from the game.
A tense first half continued with the champions in the ascendency, employing their kicking game to good effect and winning the collisions.
Burrell was dumped in his own 22 and Sexton sent opposite number Ford hurtling backwards in the tackle, but the Lions fly-half could only land one of the ensuing penalties.
The pressure continued and Ireland began to expand their game, looking for width more often as England struggled to escape their 22 until smart thinking from Jack Nowell swept them out of danger.
Brilliant work from Alex Goode, who collected the ball from behind his own posts and broke free, rescued England before Anthony Watson found space only to fling out a wild pass.
Ireland's execution during the passage of play that led to Henshaw's try was a lesson in efficiency that would have made the All Blacks proud.
Sexton capitalised on a turnover by chipping into the corner, Watson was collared and green shirts piled over at the ruck to win the ball back for a second time.
Having pounded at the English defence, it became Murray's turn to kick and with the ball hanging in the air Goode was out-jumped by Henshaw, who touched down with Sexton converting
Two penalties by Ford gave England a glimmer of hope, but that was extinguished amid Ireland's determination to keep their line intact as the Red Rose slumped to their first defeat of the Championship to leave their title hopes hanging by a thread.