Six Nations: Scotland pay the penalty as Halfpenny cashes in for Wales

They used to say that if you whistled down any Welsh mine you would find a fly-half of world-beating potential. The pits in the Principality might have closed now – the vast majority, at any rate – but if they open them up there could be a new job for Craig Joubert.

The South African referee blew his whistle so frequently in the west end of Edinburgh yesterday he was in danger of losing his pea. It was a blessed relief to all when the 80 minutes was up and the interminable symphony came to an end.

There was also relief among those clad in red on the pitch, and the visiting hordes in the stands, when the final blast confirmed a Welsh victory from this thrill-less penalty-fest of a contest in the chill of the Scottish capital. Having plundered the only try – courtesy of Richard Hibbard, the hooker Scotland's interim head coach, Scott Johnson, once deemed too fat for the international fray – and dominated at scrum-time, they deserved their success and their shot at holding on to the Six Nations title in the championship decider in Cardiff next Saturday.

It was an historic occasion of sorts: a fifth successive away win in the competition was a record for Wales. It was also an occasion on which the referee was a candidate for man of the match, in the respect that his fastidious officiating dominated proceedings.

There were an incredible 19 shots at goal, 18 of them from penalties. Leigh Halfpenny missed three penalties in a row but still finished with 23 points, courtesy of seven penalty successes and a conversion. Greig Laidlaw kicked six out of eight for the Scots.

The Red Hot Chilli Pipers did their best to warm the capacity crowd before kick-off but the mercury had dipped below zero before Dan Biggar got proceedings under way. Not that any assets were frozen in the visiting pack. Indeed, from a line-out on the left the Welsh forwards mounted a succession of drives up the middle that yielded a mini-series of scrums and a Scottish front-row collapse.

From a range of 15 yards, Halfpenny was on the money with the ensuing penalty. If that amounted to something of a flying start for the Welsh they proceeded to get caught standing still. From the restart, Ryan Jones, Wales's captain and blindside flanker, entered a ruck from the side and Laidlaw banged over an equalising penalty from 40 yards.

That put wind in the Caledonian sails, and when the Welsh defence strayed offside Laidlaw stepped up to convert the penalty and furnish Scotland with a 6-3 lead after 13 minutes. Worse was to follow for the visitors. Three times in five minutes Halfpenny was off the mark from his kicking tee – pushing a penalty wide to the right, then wide to the left, than smacking the right post.

Still, Welsh nerves were settled in the 23rd minute when they managed to cross the home whitewash. Left- wing George North did the initial damage with a shimmy past Richie Gray and a half-break on the right. The Welsh pack followed up, the hirsute Hibbard applying the finishing touch from close range. Halfpenny regained his touch with the boot, landing the touchline conversion.

Laidlaw reduced the deficit to 10-9 with his third successful penalty but Scotland suffered a major blow just before the half-hour mark, Gray catching his studs in the turf and departing with a knee problem that could have implications on his Lions selection prospects.

In Duncan Weir, Scotland have a former Celtic youth-team player, and the Glasgow fly-half, making his first start for his country, showed his footballing skills as he chipped over the Welsh defence and fly-hacked on, forcing Biggar to take the ball across the try-line for a five-metre scrum. All that the Scots could glean from the attack, though, was another Laidlaw penalty and, though that was duly despatched, a Halfpenny penalty gave Wales a 13-12 advantage at the interval.

From there on it was always likely to be nip and tuck. Laidlaw missed a penalty from distance. Halfpenny despatched one from close range. Laidlaw answered in kind. Then Halfpenny landed another three-pointer, and another. Then Laidlaw responded.

All of which left Wales 22-18 up going into the final quarter, and the crowd in a state of deep-frozen boredom. Warren Gatland happened to be among them. If the Lions' head coach knows anything, it is that Halfpenny can kick. Two further penalties from the Welsh No 15 completed the job.