Wales stand one win away from a Grand Slam in Warren Gatland's final Six Nations campaign, after they battled to an 18-11 victory over injury-hit Scotland at Murrayfield.
First-half tries from Josh Adams and Jonathan Davies ultimately proved enough to secure victory for Wales, but they were made to work incredibly hard by opponents who suffered abysmal luck on Saturday.
Already shorn of star full-back Stuart Hogg, Scotland lost their entire starting back three to injury during the contest, with Tommy Seymour, Blair Kinghorn and try-scorer Darcy Graham all forced off.
Gregor Townsend's men were nevertheless the much stronger team after the interval, but Wales clung on for a 13th win in a row and can now complete a third Grand Slam under Gatland, who will leave his role following this year's World Cup, when they host reigning champions Ireland in Cardiff next Saturday.
In the lead-up to this fixture, Gatland said his players had been distracted by talk of a proposed merger between the Ospreys and Scarlets, but Wales looked totally focused as they built a 15-6 lead in the opening 40 minutes.
Scotland started well and took the lead through an 11th-minute penalty from the fit-again Finn Russell, but Wales hit back immediately with the game's first try, Adams surging past Kinghorn on the left flank after taking a pass from Davies that appeared forward.
Things were soon looking bleak for the hosts, who lost Seymour and Kinghorn either side of Davies rounding off a superb 24-phase move to extend Wales' lead, after Russell and Gareth Anscombe had exchanged three-pointers.
However, Scotland fought back impressively after the interval and Graham - who had produced a wonderful jinking run in the first half to no avail - went over on the right flank to narrow his side's deficit to four points, following an injury that forced Wales full-back Liam Williams to be replaced.
Graham was the next man to join the casualty list after a clumsy Adams knock-on prevented Wales from converting a great opportunity on the counter-attack, but Scotland remained firmly on the front foot as a tense contest neared its conclusion.
Wales were not to be denied, though, and their clinical display was summed up when Anscombe landed an 80th-minute penalty after waves of Scotland pressure had been repelled.