Smith would welcome a revival from the giants of the north, United and Aberdeen, who have both gone without a league title since the 1980s.

Celtic and Rangers have shared the SPL titles since Aberdeen were last champions in 1985, and their supremacy has rarely been challenged.

It took managers of the calibre of Jim McLean and the pre-knighthood Alex Ferguson to make forces of United and Aberdeen.

But ahead of his team's CIS Insurance Cup final date with United, Smith is hopeful the clubs once tagged 'the New Firm' can rise again.

"It would benefit Scottish football if there was more than a third team - if there was a fourth team, a fifth team, a sixth team," said Smith.

"I think we need that.

"In the recent history of football, Dundee United and Aberdeen have been the clubs who have come closest to Rangers and Celtic, and even that was in the '80s."

Tomorrow's Hampden showdown has been tagged 'the Eddie Thompson final', as the cancer-suffering United chairman prepares to see Craig Levein's Tannadice troops contest the season's first silverware.

Smith admires Thompson for setting United back on course to challenge for the Scottish game's big prizes.

"Eddie Thompson is to be congratulated for coming in and attempting to lift Dundee United back to that level," Smith said.

"It's taken them a little bit of time and I think in the current manager they've got somebody who can bring that level of consistency back to the club again.

"In Scotland we need them all. Whether we need them winning trophies or not is another thing!"

Smith, who served United as a player and then as assistant manager to the legendary McLean, will not let strong feelings for his former club affect him tomorrow.

Rangers will be bidding to land their first trophy since winning the same competition three years ago, an eternity by their very high standards.

It could also be the first leg of a 'quadruple', with the Scottish Premier League, Scottish Cup and UEFA Cup trophies also in Rangers' sights.

United's ambitions are more modest - securing third place in the SPL will be their target once this weekend is out of the way - but Smith senses that Levein has what it takes to make United more than one-season wonders.

He even sees a reflection of McLean's management style in the methods of the current United boss.

"Craig has brought back a bit of the Jim McLean-type football which made Dundee United so successful," said 60-year-old Smith.

Thompson, whose strong working relationship with Levein saw the manager promoted to the club's board in January, has plans in place to hand over control of United to his family.

There has been plenty made of a possible 'Thompson factor' giving United an added incentive to win tomorrow's game, but Smith said: "I don't think it will have a bearing on the game.

"I know Eddie well from my last period at Dundee United. We all know the fight that he's had in recent years and everyone would feel for that.

"But when it comes to football I don't think it will have a great effect.

"Obviously it'll be a fairly emotional time for both him and his family but I don't think it will affect the footballing side too much."

Rangers will start as firm favourites, even if the cup-tied Steven Naismith, injured Daniel Cousin, and suspended Charlie Adam and Nacho Novo are unavailable to boss Smith.

Their line-up will still be formidable, as the depth of the Rangers squad means they can call on players of comparable quality.

United would struggle under similar circumstances, and Smith has personal experience of the gulf which exists between Rangers and the clubs who aspire to match them.

He knows just what tomorrow's occasion will mean to United, who last clinched major silverware when they won the Scottish Cup in 1994.

"I spent all my playing career at provincial clubs," said Smith, who also turned out for Dumbarton, "and I got to one final in that time.

"Over a 20-year period that's not a lot.

"You don't get that many opportunities so when it comes along you want you try to make the most of it. I'm sure that'll be the case on Sunday."