Rangers manager Walter Smith accepts Dundee United could wreck his team's bid for the domestic treble in Sunday's CIS Insurance Cup final.

Rangers' 20-game unbeaten run came to an end on Thursday, even though the 1-0 defeat to Werder Bremen in Germany felt as good as a win as they reached the UEFA Cup quarter-finals.

Smith will send his side into battle with United fully aware Craig Levein's side will be up for the occasion.

His mission in training on Saturday will be to ensure his own players are equally fired up for the occasion.

Smith, a former United player and coach himself, has followed Levein's progress attentively since the ex-Hearts boss took charge at Tannadice in October 2006.

He knows Levein's players could take advantage if there is anything disjointed about Rangers' performance at Hampden.

"If we talk about the confidence in the Rangers camp being reasonably high, I think it'll be every bit as high in the Dundee United camp," Smith said.

He added: "Craig Levein took over at Dundee United just shortly before I came back to Rangers and Craig has turned their fortunes around as well.

"They're having an extremely good season, and I always remember my time there.

"We didn't get to that many finals overall and you look forward to that, and I think Craig and his squad will look forward, as we will, to the first final of the season.

"Both clubs have been far more consistent this season and played to a better level than they have done previously.

"So a good final looks like it's about to take place."

Levein's side are fighting for third place in the Clydesdale Bank Premier League.

Smith said: "He's brought stability back to the club, I don't think there's any doubt about that.

"Like we all do in football, he's had his ups and downs in the managerial stakes.

"But there's no doubt he's an excellent manager. He had no real need to prove that, but he's doing it again and because it's my old club I always like to see them do well."

Smith welcomed United's draw at Celtic on Wednesday, which strengthened Rangers' chances of clinching the SPL title.

Celtic could go top of the league today on goal difference by beating Motherwell at Fir Park, but Rangers would have two games in hand.

United's midweek shut-out at Parkhead could be a crucial result come the end of the season.

"It was a terrific result for them there," said Smith.

"United, like ourselves, are a difficult team to overcome, and going to Celtic Park is one of the hardest places you can go to get a result, and they managed to do that."

Smith will be without the injured Daniel Cousin, the suspended Charlie Adam and Nacho Novo, and the cup-tied Steven Naismith tomorrow.

Defenders Steven Smith and Andy Webster may also miss out, despite returning to full training after long injury lay-offs.

Smith suggests both men should look to United captain Lee Wilkie for inspiration as they plot their returns to senior action.

Wilkie's career was in doubt when he sustained two serious injuries which left him without a cruciate knee ligament.

Smith said of Smith and Webster: "If they can look at Lee Wilkie, you can see he's stuck to his task of coming back.

"It's not been easy for him, but he's back and here he gets an opportunity to play in a cup final, and I'm sure it'll be a big boost for him."

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