Wales remain on course for the Grand Slam but they were given an almighty scare by Scotland before emerging 18-11 winners at BT Murrayfield.
Only Ireland now stand between the Welsh and a third Grand Slam under the stewardship of Warren Gatland in his final Guinness Six Nations campaign.
First-half tries from Josh Adams and Jonathan Davies proved enough here, but having led 15-6 at half-time, Wales were made to sweat in the second half.
Darcy Graham’s first Test try was reward for the huge Scottish pressure, but in the end it was the Welsh defence that was just too good as they held on for the win with Gareth Anscombe’s late penalty sealing the win.
As a result, Cardiff next week will see Gatland and his team go for the Grand Slam against Ireland, looking to finish off his career with Wales as he started it.
Scotland enjoyed some early possession and hit the front when Josh Navidi was penalised for offside. Finn Russell, taking on kicking duties in the absence of Greig Laidlaw made no mistake.
But having been under pressure for much of the opening exchanges, Wales were clinical with their first real chance. In midfield the ball was spread to Davies and he played the two on one perfectly to put Adams away. The winger needed no second invitation, and then shrugged off a weak tackle from Blair Kinghorn to score. Anscombe converted to make it 7-3 to the visitors.
Scotland had been dealt an early blow with Jamie Ritchie off for a HIA, with replacement Hamish Watson then also needing to be stitched up which led to Fraser Brown filling in at flanker.
Ritchie returned, but the back three was hit hard when Tommy Seymour and then Kinghorn were forced off, leading to a reshuffle as Byron McGuigan came onto the wing and Adam Hastings to full-back.
Despite that, they did hit back, with some brilliant feet from Graham on his first Test start. The winger was fed the ball under pressure just outside the 22 but danced his way through the first line of defence before eventually Alun Wyn Jones got back to haul him down.
The Scots could not capitalise, with Wales eventually penalised and Russell adding his second penalty.
The four-point lead was quickly restored, Anscombe slotting a long-range penalty before Wales got their second try.
This was one had an air of inevitability about it. After one initial break, they got into the 22, and then they just went through the phases, inching towards the line before Jonathan Davies punched his way over.
Anscombe pulled his conversion, and then pushed a penalty against the post, but Wales were in control at 15-6 at the break.
Scotland had spent the latter stages of the first half on the back foot, and needed a response to start the second.
They got one with a remarkable break by Allan Dell, running fully 30 metres after being put away by Russell. He was eventually brought down by Liam Williams, who injured himself in the tackle.
Scotland poured forward but could not take advantage of the territory, with two wayward passes from Russell seeing the move come to nothing.
The fly-half made up for it soon after however. After a rolling maul it was his inside pass, as Davies lined him up, that put McGuigan through. He then fed Hastings, who played the overlap well to put Graham over.
From there Scotland gave it everything, with Watson making a huge impact off the bench as he appeared to barrel over defenders with every run.
However each time it seemed the Welsh defence would finally be breached, one more defender would appear to knock back a Scottish attacker.
Scotland captain Stuart McInally said: “We’re massively disappointed with that. We had chances to win the game and we just weren’t quite accurate enough. We cost ourselves defensively in the first-half, gave them a couple of cheap tries and we just couldn’t break them down in the second-half.
“It was a big step up from last week but we’re still massively disappointed with that.”
Wales centre and man of the match Hadleigh Parkes: “Scotland really chucked it at us in that second half, but the forwards defended really well and the backs complemented them all right.
“It was a win we had to really dig deep for. The feeling in the team is amazing at the moment, we enjoy each others’ company and working hard for each other.
“Next week is very exciting, it is going to be amazing for all of us. In our careers it doesn’t come along very often.
“But we will enjoy this win first of all and then look forward to next week.”
For much of the second half it looked as though Welsh defence would stifle Scotland as they have so often in recent meetings. Eventually though, Scotland did find a way through, and it was spectacular. Off a rolling maul they turned to the backs with Peter Horne finding Finn Russell just as Jonathan Davies reached him. The fly-half slipped the ball back inside to Byron McGuigan, who raced through a gap. He then found Adam Hastings who in turn fed Darcy Graham for a wonderful try.
Adam Beard’s unbeaten record in Tests goes on, and although it was in doubt for a while, he made a real difference in this game. The Ospreys lock is the natural successor to Luke Charteris when it comes to his maul defence and he caused Scotland all sorts of problems in that sector. His long arms, and ability to work through the heart of a maul allowed Wales to negate that part of the Scottish attack. It was no coincidence that on almost the only occasion he didn’t get his hands on the ball in a Scottish maul, the home side got over.
