Wales trounce 14-man Scotland in Six Nations as Stuart Hogg sees red

If only points difference had been relevant to this one, Wales might yet have won that third consecutive title. As it was, they ended up running in tries left, right and centre, as if their lives depended on it – the carnival atmosphere under the closed roof intensifying with each – as Wales celebrated their 100th Test at the Millennium Stadium, and Gethin Jenkins's record 105th cap, in some style. But it was a hollower victory than it should have been, and it came at a price. Sam Warburton dislocated his shoulder towards the end and, like Leigh Halfpenny, he is sure to miss Wales's tour to South Africa in the summer.

This fixture is traditionally one of the more entertaining, try-laden affairs of the old championship. This one may have kept up the tradition on the try front, but it was horribly compromised on the entertainment front by the red card shown to Stuart Hogg midway through the first half for an ugly shoulder charge on Dan Biggar. It meant that a frustrating Six Nations for Scotland – albeit not without its moments – was destined to end in humiliation long before it actually did. As the tries flowed, five of them in 20 minutes either side of half-time, the cheers may have rung as loudly as they tend to in this great cauldron of a stadium, but the exhibition meant very little.

Any feeling that this game was the non-event of the now-routine "Super Saturday" at the end of a Six Nations was consolidated by that fateful rush of blood to the head – or shoulder – of Hogg in the 23rd minute. Chasing his own kick, Hogg was too late to stop Dan Biggar from clearing, and followed through with his shoulder. Biggar was hit square in the face by it, in a vicious collision. The referee did not hesitate to show him the yellow card.

Then came the interesting part. We have seen referees watch a TMO review and come to his own decision, but what happened next was new territory. Jérôme Garcès caught sight of the replay on the big screen. The crowd's outraged reaction no doubt pricked his attention, or maybe it is a referee's secret indulgence to check each of his decisions when they're replayed on high. Either way, Garcès was so shocked by his latest that he marched over to the touchline to rectify it by upgrading Hogg's yellow to a red.

It probably was a red. Hogg led with his shoulder, although whether he intended to catch Biggar in the face with it is a moot point. In slow motion on a big screen, with 75,000 braying fans in your ear, it looked bad. More to the point, yet another improvised precedent has been set regarding the referee and his use of big-screen replays. One day they'll be doing it all off the telly. And have we ever before seen a referee change his mind like that? This will do little to discourage football-style lobbying of a referee by the players.

At 10-3, after Liam Williams's 15th-minute try, the game had been poised, but any balance – and there was some – fell away as Wales ran in two more tries before the break, both exploiting the lack of numbers in Scotland's defence out wide. Liam Williams's break paved the way for the first of those, finished by George North, and Jamie Roberts scored the other just before half-time, after Davies had danced down the touchline.

North and Roberts scored another try each after the break, North's within a minute of the restart, Roberts's eight minutes in. The latter was a magnificent length-of-the-field affair. After an overthrown Scotland lineout, Williams, the man of the match in the absence of Halfpenny, galloped clear from his own 22, through those sparsely populated spaces in Scotland's wide defence, before some smart support play by Davies and Toby Faletau put Roberts away.

Faletau scored six minutes later, after he strolled in, but by then the sick feeling that these duck shoots tend to elicit was well established in the stomach. Scotland dug in thereafter and exerted some consistent pressure, particularly in the scrum, but it was futile. Another try exploiting the lack of a Scottish full-back was finished by Rhodri Williams in the last 10 minutes to bring up the 50 and confirm Scotland's heaviest defeat in the championship.

Conversely, this was Wales's biggest victory, but it was an ugly, lovely win, as Dylan Thomas might have put it, high on artistic merit, yet rendered toothless by that unfortunate incident in the first half. But at least they take away a handsome points differential. What Scotland take from this Six Nations is harder to discern.