Rangers boss Walter Smith has spoken of his frustration over criticism from supporters - despite his team's bid for four trophies.The Gers were booed off by some fans following their 0-0 draw with Sporting Lisbon in the first leg of their UEFA Cup quarter-final on Thursday.

Smith admits it has been a troubling feature of a season that has seen Rangers reach the last eight of a European competition for the first time in 15 years, while being favourites to win a domestic treble.

"It's been happening since the first game of the season when we were booed off at half-time against Zeta," said the former Scotland boss.

"That seems to be the way people want to support the club. It is a wee bit of a disappointing factor in the sense that when we go away from home we get terrific backing.

"When we come to home games, right from the very start, there seems to be dissatisfaction.

"If there continues to be dissatisfaction, there is only one thing that happens, isn't there?

"The manager normally leaves when you have a lot of dissatisfied supporters.

"We seem to have a lot of dissatisfied supporters at the moment, and that is maybe something we have to put up with."

Rangers created few chances against the Portuguese team, but Smith insists that is when they need the fans the most.

"At a period of time when everything is going well in a game, that is not really the time when you need the support," he said.

"You need the support when you are not doing well.

"From a managerial point of view, that is a situation that happens. Whether you find it understandable is another thing.

"Invariably, if a manager brings the subject up, you get an outcry of 'you should be doing better'. We haven't to criticise anything at all.

"Supporters pay their money and are entitled to react in the manner they do. At times it can be difficult to understand, and I don't think it helps the club overall."

Smith's cautious tactics of playing one up front may also have upset some fans.

But he believes the players who ended a three-year wait for a trophy last month with a CIS Cup final win over Dundee United will find the criticism baffling.

"I appreciate the demands," he said.

"I keep saying to the players 'if you can't meet the demands you are not going to be here'.

"That is from the chairman all the way down. But somewhere along the line there has to be a level of understanding, and there does not seem to be at the present moment.

"A lot of the boys who are new must find it hard to understand. For a club that has not had recent success, all of a sudden they have an opportunity to turn it around - and they are still hearing that."

Rangers continue their Scottish Premier League charge with a trip to Tannadice to face Dundee United on Sunday.

Charlie Adam is out, but French striker Daniel Cousin may return following a broken jaw.

"He is close to playing," Smith reported.

"If he is not allowed to play this week at some stage, I don't think it will be any longer than next weekend.

"Charlie Adam damaged his knee in training. We are waiting on the specialist's assessment, but it will certainly keep him out for a good few weeks."

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