The Welsh have not won their opening game in the tournament since they triumphed in Edinburgh in 1997.
And it is 10 years since they have launched their campaign with a home victory - again Scotland were the fall guys - when they went on to celebrate their last championship triumph.
But Hansen is confident Wales can end that record at the Millennium Stadium as long as they pick-up where they left off in the Rugby World Cup last October when they gave New Zealand and England almighty frights.
"The players are coming off two good performances so they will go into the game against Scotland with some confidence," said Hansen, who returns to New Zealand to take up a coaching post with the All Blacks at the end of this year's tournament.
"If they believe in themselves and go out and demonstrate that then anything could happen. They are good enough to win the game as long as they play to the best of their ability."
Wales will face a Scottish side which is rebuilding under new coach Matt Williams after seeing several big-name stars retire at the end of the World Cup.
But Hansen is aware that the Scottish pack is a formidable force which Wales will have to come to terms with if they are to unleash the pace and trickery of their potent back division.
"The Scottish pack is one of the best in the world," added Hansen, whose side suffered a whitewash last year.
"They have proved that over the years and although there has been one of two changes they have a lot of experience as a group. It is the key to the game.
"We want to play the game that suits our style which is to attack. If the Scottish mind-set is to be negative, and I don't think it will be, then maybe we will have to start kicking the ball into space.
"It is up to us to pick up where we left off in the World Cup. The players have done it on the training pitch but there is a big difference between doing it in training and doing it in a game.
"We are more optimistic than we were last year. We are further down the track this time and we understand the game better, physically we are in good shape so we want to get away to a good start."
Hansen has made six changes to the side that went down to an heroic defeat against England in the Rugby World Cup quarter-final in Brisbane.
Prop Duncan Jones and centre Sonny Parker return after injury while Rhys Williams replaces injured wing Mark Jones and flanker Martyn Williams is recalled at the expense of Jonathan Thomas, one of the Welsh stars Down Under.
Wales though also suffered a blow with key forwards Robin McBryde (back) and Robert Sidoli (groin) sidelined by injury with Mefin Davies and 34-year-old veteran Gareth Llewellyn their respective replacements.
The roof of the 74,000 seater Millennium Stadium could be closed with both coaches saying they would prefer it to be shut given the unpredictable weather.
"There is no point having a great stadium with a roof on if you do not want to close it," said Hansen. "If the Scots also want it shut then it should not be a problem."