They say a week is a long time in politics but it can be an eternity in football. Just ask Celtic.

Last weekend the doom and gloom merchants abounded as the champions drew a blank for the second successive game after losing to Kilmarnock in the League Cup and failing to beat bottom-of-the-table St Johnstone at home in the Premiership. The next stop for Brendan Rodgers men is Ibrox.

Early forecasters were predicting a comfortable win for the home side. Rodgers was under pressure. Celtic also needed to spend money in the remaining few days of the transfer window to offset the horrendous injury list they were carrying. Fast forward a few days and all has changed.

The mood music is suddenly very different regarding Celtic's trip to Govan. The acquisition of one-time Rangers transfer target Luis Palma, central defender Nat Phillips from Liverpool, the impending arrival of Paulo Bernardo from Benfica and possibly more incomings before the window shuts has given the club a spring in their step.

Allied to that, Celtic are now Scotland's sole representatives in the Champions League group stage after Rangers were turfed out at the play-off phase after being bludgeoned 5-1 by PSV Eindhoven to crash out 7-3 on aggregate. All of sudden it is Michael Beale and his Rangers team who are the ones feeling the heat.

Former Celtic defender Ramon Vega faced Rangers three times in his five-month spell with Martin O'Neill's men. He won them all. Vega knows exactly what it is like to run out into the cauldron of Ibrox and get a result.

READ MORE: Ramon Vega: Upstaged by Henrik Larsson on nerve-shredding Celtic debut, a joyous treble and a painful departure

Despite what the form book and pundits may suggest, the Swiss star feels that Rodgers' men can triumph at Ibrox and kickstart their season into gear in the process and that no extra motivation will be needed.

Vega said: "This is the day when the Celtic players puff out their chests and embrace the occasion and enjoy it. When you go to a place Ibrox as a Celtic player it is not even a question that you want to leave the home of your rivals as a winner.

"You don't need to motivate the players as it is a given. Since the moment they left the field after drawing 0-0 with St Johnstone the focus of attention will have turned to the Ibrox game. The players will have felt it all week in training as the intensity levels will have been heightened and that is a good pressure. It is a positive pressure. The expectations of the fans will be high too. Every derby becomes the most important one as the Celtic players and manager will not want to come off the pitch a loser.

"The pressure that you feel is great. It is good for team morale as these are the kind of games that show players why they signed for Celtic in the first place.

"Celtic have not had a great start to the campaign under Rodgers but this is the kind of game where it could all click into gear and kickstart your season. Of course, it can go the other way but that will not enter any Celtic players' heads on Sunday.

"They will be going to Ibrox to rediscover their goalscoring touch and get the winning formula back and there is no doubt they can do that. There has been some disruption in the lead-up to this match as certain players have left the club and the injury list just seems to be growing at an alarming rate but once you pull that Celtic shirt on at Ibrox nothing else matters.

"It doesn't matter who is on the team or not on the team. The players play for that Celtic crest and badge on the shirt and for the supporters who will be conspicuous by their absence. What more cause do you need to go and get a result at the home of your fierce city rivals?

"It doesn't matter if there are no Celtic fans in attendance as that just gives you an extra reason to spur you on to success.

Vega reckons that the one thing that could sway the derby in Celtic's favour is the need for Rodgers' men to show their true character.

The 52-year-old former Tottenham Hotspur stopper and Switzerland international said: "When I played for Celtic we had big characters in the dressing room - Chris Sutton, Henrik Larsson, Neil Lennon, Paul Lambert, Alan Thompson and myself to an extent - we weren't there to be nice guys and stand on ceremony we were there to do the job.

"Make no mistake Rodgers will send whatever set of players out to battle at Ibrox confident that they can get the job done. Each player will have the responsibility to give their all and represent the shirt they are wearing to the best of their ability. When the dressing room has strong characters that can influence the winning mentality and formula on the pitch.

"That's what Celtic need on Sunday. They need to be strong in their mind. I am not talking about arrogance or ego per se but sometimes those qualities are required to get you over the finish line in these kinds of matches. That's crucially important.

"Brendan will be a wonderful calming influence on the Celtic players and a lot of how the team will play on the day will come down to how he comes across in the dressing room.

"This is a major factor and if he feels that these players are man enough and responsible to carry out the task at hand then he won't have to do all that much. He will trust them implicitly to execute his game plan to the letter of the law.

"Brendan has to manage that psychological side of it all and send his team out in the best possible frame of mind."

Vega admits that he loves talking about his own Ibrox experience as he was part of a Celtic team that dismantled their rivals 3-0 at Ibrox back in April 2001 on a day when Larsson notched his 50th goal of the campaign and Lubomir Moravcik turned in an attacking midfield masterclass to claim a brace.

He said: "Fucking hell, how can you forget something like that? It was absolutely delightful. This was the game that you wanted to be involved in as a player. These are the games that create heroes and make football so enjoyable for a player. As a footballer, you crave moments like that.

"I was fortunate to experience what I did with Celtic. I was lucky to have an opportunity to play for a club like Celtic and experienced that feeling of being in a dressing room with a group of guys who hammered Rangers in their own backyard. It is a very unique derby and it is absolutely electrifying. I never got a wink of sleep the night before I was so excited.

"My message to the Celtic players would be to say that registering a win at Ibrox is more than possible. This could be the turning point in Celtic's season. Go out there and grab that opportunity and what better place to do it than at Ibrox? You cannot choose a better game than this to do the business."

Celtic Way:

READ MORE: John Hughes talks Celtic, Tommy Burns, Pep Guardiola, Rod Stewart and scoring against Rangers - The Big Interview

Former Celtic defender John Hughes was on commentary duty in the gantry for the BBC on the last league occasion at Ibrox when Beale's men stuffed the men in green and white 3-0. He once scored a last-gasp equaliser during a 1-1 draw in Govan in 1997 to hand then Celtic boss Tommy Burns's team a lifeline in their quest to deny Rangers their ninth straight title. The ex-Falkirk, Hibs and Inverness manager insists that Celtic are well capable of winning especially now that Rodgers is back at the helm.

Hughes said: "Celtic have not had a great start to the season and they are entering the lion's den at Ibrox but they are still top of the league and they have a first-class manager at the helm.

"After Ange Postecoglou left the club Celtic could not have hired a better man than Brendan. He knows the club inside out, he knows the players and he is a great football man.

"He will be working overtime in terms of shape, style. discipline, you name it, he will be instilling a quiet confidence in his players and there will be a sense of trepidation as well going to Ibrox but that is a good thing in football.

"The Celtic players have a great belief, trust and respect in one another and that all stems from a manager whose record in football is outstanding. Rangers are still bedding players in and will present a bigger challenge to Celtic this season.

"Nobody needs to tell the Celtic players how disappointing the start to the season has been. They will have heard the boos at the final whistle against St Johnstone. They are born winners and they will feel that they have let the manager, the club and the supporters down. My message would be to stick together.

"Regardless of the last two results if there is one thing that Rodgers will give those players before they step out at Ibrox on Sunday is belief. Rodgers will know that if his team come out at Ibrox and turn it on then they can win the game.

"Celtic are in right good hands with Rodgers. The best if the truth be told. The way his teams play, and the way he conducts himself is just second to none.

"Celtic have recruited a brilliant manager and Scottish football should feel privileged and lucky to have that managerial quality back in our league. Rodgers is one of the best managers in British football and he is back plying his trade in Scotland."

Never mind the mood music all week.

An away win at Ibrox on Sunday - as well as the opening of a four-point gap at the top of the Scottish Premiership table - will be sweet music to Rodgers as well as the absent Celtic supporters' ears.