THERE is a first time for everything.

For Kenny McDowall, that moment is approaching.

The 51-year-old is no stranger to the intricacies, the pressures of life at the Old Firm after almost two decades in the Glasgow goldfish bowl. On Sunday, McDowall will either sink or swim.

Having begun his coaching career in the green half of the city, his time in the dugout will reach a new peak when he steps out at Hampden with the Rangers crest on his chest.

The decision to hand in his notice earlier this month marked the beginning of the end for McDowall at Ibrox.

He will soon bring the curtain down on an association with the club that has taken him everywhere from Manchester to Montrose since Walter Smith brought him from Parkhead to Ibrox eight years ago.

He has never looked comfortable since replacing his friend, and former manager, Ally McCoist at the helm last year but the passions will surely be stirred when he leads his side out to face Celtic in the League Cup semi-final.

"Anyone that gets the opportunity will get to know what it is like. You don't need any laxatives in an Old Firm game!," Smith said.

"It is the same for both managers. Kenny is taking charge of the team at the moment and Ronny [Deila] is in charge at Celtic. It is their first game in charge.

"Kenny at least knows what it is like, he has experienced it from a coaching perspective. So, for him, it will not be a major surprise.

"For a lot of the people at Celtic, it will be the first time. For a lot of people at Rangers it will be the first time that they have played an Old Firm game so it will be interesting to see how they handle it."

McDowall and Deila may be in uncharted waters as they experience the build-up to their first derby day as manager but it is a course Smith has navigated on many occasions.

His Old Firm record ranks him alongside the greatest managers to ever take to either dugout as the matches have given him some of his finest moments in the game.

The lapse of three years between the last meeting between the clubs will not have diminished the rivalry and Smith knows it won't have eased the burden on McDowall or his Parkhead counterpart, either.

He said: "I used to love it at time up when we won. I can't say that it was one of those games that you really looked forward to taking part in.

"You felt it, there is no doubt about that. It doesn't matter what anyone says, players are lucky to go out on the pitch and play.

"But from a managerial point of view, in my career there was nothing like it. You go to England and there is Everton v Liverpool, Manchester United v Manchester City, I have experienced the two of them.

"The Old Firm game has an edge to it that is missing in these matches. I can't say that I miss them.

"On the other hand I say they are necessary. They are necessary for everyone else except maybe the two managers."

It is on McDowall's shoulders where the greatest pressure will rest at Hampden but the first blow of the whistle will also be a signal for his players to stand up and be counted.

Too often during Rangers' rise through the lower leagues, and this season in particular, performance levels have fallen well short of what is expected, and demanded, at Ibrox.

Wins over St Johnstone and Inverness Caledonian Thistle this term prove that this squad is capable of seeing off Premiership opposition.

But Celtic will provide McDowall's players with the biggest test of the campaign, and perhaps the biggest of their careers, as they look to defy the odds and satisfy the Light Blue legions.

"Playing for Rangers is not easy, and Celtic," Smith said.

"It is not an easy circumstance and you have got to be a decent standard of player. The boys that are at Rangers are finding that out.

"The lack of creation is something that Rangers have had to try and overcome over the season.

"The Premier Division teams will come and play them, but the majority of First Division teams will make sure they are nice and tight and it makes it a bit more awkward for them. Celtic will obviously come and play them.

"Celtic are obvious favourites to win the game but I think it might be tighter than a lot of people imagine. For a lot of the Rangers boys, it will be their first experience and they will want to do well.

"Celtic are rightly favourites to win the game but I think it will be closer than people imagine it will be."

While Rangers fans will head to Hampden more in hope than expectation this weekend, the same will not be said when they resume their battle for supremacy in the Premiership upon their return to that level.

The gulf between the Gers and Celtic, both on and off the park, is arguably the widest it has been in since the Glasgow giants first did battle more than a century ago.

There is no doubt that, despite the rivalry, these two have missed each other in recent years and Smith reckons the top flight has been a poorer place without his former club as well.

He said: "This year we are seeing a better domestic league that is helping bring back a few people to the game but it still needs Rangers to get back into the league again.

"It still needs Rangers to get back to what we would know as a Rangers team and a Rangers club. The sooner that happens the better for Scotland.

"The Old Firm game does bring up some elements that we would rather do without but, overall, it is a big loss to us that we don't have the Old Firm fighting for Championships."