Scotland legend Andy Irvine believes his countrymen can spoil Wales' Grand Slam party with a shock win on Sunday.
Scotland make life very difficult for Wales at Murrayfield
"There's going to be a lot of pressure on Wales this weekend because as far as Scotland are concerned, they can't get any worse," he told BBC Wales Sport.
"Wales obviously have to win this one to go into a possible Grand Slam final with Ireland next week.
"But these are the sort of scenarios where Scotland do well, when they are completely written off."
Irvine, who captained Scotland 15 times in 51 appearances, has first-hand experience of upsetting an unbeaten Wales side at Murrayfield.
The former Lions full-back played in the famous 12-10 victory in 1975 where a then world record crowd of just over 104,000 packed into the stands.
Wales headed north with wins over England and France under their belts, and the expectant Welsh fans were out in force.
"It was a tremendous day," recalls Irvine. "I remember we went out to warm-up about an hour and a quarter before kick-off and the stadium was already completely full.
"We looked at each other and said 'have we got the time wrong here?'. It was amazing."
Although ensuring an electric atmosphere, the overcrowding could have led to a serious tragedy.
Realising they had witnessed a lucky escape, the rugby authorities acted quickly to make all subsequent internationals all-ticket affairs.
"I think it was safer on the field actually," said Wales captain that day Mervyn Davies.
"There are some 40,000 Welshmen travelling to Scotland this weekend, well there was actually 40,000 Welshmen in the ground that day!
"Those were the days when you could buy a ticket on the gate and go into the ground.
"We went there to keep on course to win a triple crown but came unstuck - as many sides have done in Scotland over the years."
Wales' record at Murrayfield certainly makes for distressing reading for the current crop of players.
One victory at Murrayfield in the last 20 years does not exactly do much for confidence, even if the side is riding high after three successive wins.
Another mass exodus form Wales to the Scottish capital is expected again this weekend, and Davies is confident the travelling hordes will not come home disappointed.
"My playing record is Scotland is not great and I think Wales sides have been upset more in Scotland than anywhere else.
"The Scots will be typically mean - they never give you the ball to play with half the time so you're always struggling.
"But I can't see Wales coming unstuck here. If Wales play the way they have been - bold and with flair - then I can see them winning by quite a margin."
Irvine, though, is unconvinced.
The Scots have only managed a dour win in the championship so far, and he believes a tight and disciplined game with frustrate the visitors.
And if that does not work, there could be some help from above.
"They've been praying for favourable weather conditions," he said.
"I think there's going to be wind, rain and possibly snow coming so the odds are looking better for Scotland!"