There is no scope to forgive Billy Burns' inaccuracy as the premature ending in the Principality had Ireland coach Andy Farrell wide eyed and staring into the void. But the contest changed irrevocably when one blindside blew out his knee and the other walked for catching a prop's head with his "chicken wing."
Peter O'Mahony's sending off should have ruined Ireland's Grand Slam dream but it turns out that 15 man Wales were worse off for losing Dan Lydiate.
The veteran Welsh flanker was strapped and hobbled from scrum to lineout before limping ashore. Six tackles in 12 minutes was a tempo Josh Navidi was unable to replicate.
12 mins: George North fumbles Justin Tipuric's bullet pass and the ball is snatched by Josh van der Flier.
Johnny Sexton attempts to flip the burly Tomas Francis out of the ruck just as O'Mahony torpedoes into the Welsh prop, catching him on the cheek.
"That's a clear out," says referee Wayne Barnes, at first glance. "There is nothing wrong. Totally unavoidable."
These words are instantly struck from the record as TMO Tom Foley suggests a "quick look at it."
Barnes (staring at the big screen): “It’s almost like a chicken wing action. The facts are it is definitely foul play. He has come from a distance at high speed and hits him on the head. He is not in control. High danger.”
Barnes pulls out the red card: “Pete, it is still the head.”
15 mins: The Englishman spots Sexton's high tackle on Johnny Williams. "Over the shoulder, just a penalty." Wales play advantage with Hugo Keenan denying Williams' try scoring pass with a spectacular man and ball collision.
18 mins: Leigh Halfpenny's sure strike makes it 6-0.
19 mins: Williams' ferocious tackle on Garry Ringrose forces the Wales centre into the Head Injury Assessment room but this replacement takes three minutes to happen. The officials do not sanction the head on head clash.
22 mins: James Ryan also makes way for Iain Henderson with a possible head injury - the pack leader does not return - as Ireland seem completely out of luck and inspirational figures. Robbie Henshaw and Tadhg Beirne begged to differ but the numerical advantage eventually told.