The first between Wales and South Africa was turgid anti-rugby and Wayne Barnes' refereeing/coaching is still ringing in the ears. There were 21 penalties, which is more than one for every two minutes of actual action. The opening stanza was a ridiculous penalty fest. Wales were negative to a fault.
The second game might be the most perfect outbreak of exhilarating rugby in a World Cup, certainly since the French burst which dismantled the All Blacks at Twickenham in 1999.
Under knockout pressure at this level, you can't play the game better than the All Blacks did. Kieran Read's knock on off a kickoff is about the only blatant handling error to recall. It turned into a relentless onslaught with the many memorable moments including staggering ball skills from the All Blacks' replacement props.
All great performances need a signature moment, and Julian Savea's dismantling of three defenders for a try did that. But there are an awful lot of candidates for the highlight reel.
The All Blacks' search for the perfect mix of brute strength, athleticism, determination, tactics, technique and flair found its grand display cabinet.
What is it about Cardiff and the All Blacks - Bob Deans, Keith Murdoch, lineout diving, France 2007, the long winning run against Wales, and now the finest of all World Cup knockout performances?
In contrast, injury-ravaged Wales were brave but abysmal against South Africa and almost won. Their only try came form a hit-and-hope bomb.
The Springboks have, in classic style, circled the wagons. Their halfback Fourie du Preez is central to their tactics, which can be described as bash and barge, bomb and chase.
Each to their own, and victory is paramount. And rugby is not alone in deteriorating standards as World Cups progress - the FIFA tournament has come to specialise in ugly finals.
The Springboks have the ingredients of an exceptional pack, and No. 8 Duane Vermeulen was a giant against Wales, but their search for space has about as much success as the Outer Hebrides rocket programme.
Can South Africa win this semifinal? I really can't see it, which - take it from me - can be infamous last words. Do they have the right to narrow the game down to a bore - well yes, but it also meant they came perilously close to losing at Twickenham.
Here's the bottom line: The game deserves having the All Blacks make the final. With so much brave ambition in their plans, they can turn it into a show piece. Percentage, error-reducing rugby has its place, but not when there is something so much better on offer.
