Wales were able to grind out a 18-11 win against Scotland at Murrayfield for a thirteenth successive victory to set up a championship and Grand Slam decider in Cardiff next Saturday against Ireland.
The first half provided a dominant and confident display by Warren Gatland’s men as they scored two tries in clinical fashion taking two attacking chances in the first half hour to lead 15-6 at the break.
Ross Moriarty winning his 30th cap epitomised the Wales effort, combative in defence and immense going forwards as tries by Josh Adams and Jon Davies gave Wales scoreboard advantage.
The comfort of the first half was replaced by a nerve wracking second forty, as Scotland came out firing and gained the momentum to put Wales under pressure.
However, the visitors largely repelled the home side, apart from one crack when Darcy Graham went over to score, with a succession of big defensive sets.
Dragons forwards Elliot Dee and Aaron Wainwright were second half replacements for Wales as they came on for tired bodies in place of Ken Owens and Ross Moriarty and both Men of Gwent again proved they were well up to the standard of Six Nations rugby.
Both players stood up in defence and added bursts with the ball, but opportunities for Wales to keep the ball and get into the opposition half were rare. Wales did fluff one second half chance when they had a clear overlap after stealing upon possession in midfield, but as that chance passed it was left to the defence to be the difference.
The defensive line speed by Wales was so important throughout the second half in withstanding the pressure by Scotland and Wales showed great character to continue the winning habit to setup the crucial crunch clash in Cardiff next Saturday.
Scotland head coach Gregor Townsend on BBC One: "There is partly frustration but a lot of pride, we gave a true picture of what we are capable of.
"The players had to handle some things that went against them, injuries early on and reshuffling the backline and players out of position, but we showed what we were made of in that second half in terms of the rugby we want to play and in our character.
"We had enough pressure in the second half to win. Strong defences will force errors but but we forced a lot of penalties out of Wales, I think five in the 22 that should normally lead to yellow cards with that pressure, but obviously we are very frustrated that that didn’t happen."
Wales head coach Warren Gatland added, "It was a comfortable first half and then you don't get out of you own half in the second. Scotland played well and their bench was good, so you have to give them credit.
"When you look back on a Grand Slam there is always one game you think was close and that was probably today.
"We have got a dream at the moment and we will start planning for next week. We made a few errors and our line speed wasn't good in areas but it got better. It has been a tough week for the boys mentally but they dug deep and showed some character. This group have forgotten how to lose and hopefully that continues next week."