This week Celtic are celebrating their 125th anniversary. It has been an illustrious history that has now spanned one-and-a-quarter centuries, but there have not been many victories which will be remembered as fondly as this one.

Barcelona had been here before, although not for some time. Prior to Wednesday night's Champions League clash at Celtic, only Real Madrid had beaten the Catalans this term.

Indeed, every other rival apart from Jose Mourinho's men had been put to the sword by Tito Vilanova's team. Including the Glaswegians. The Scottish side had come closer than most, however, as they were edged out in the most cruel and dramatic of finales at Camp Nou in late October, conceding deep into added time as Adriano and Jordi Alba combined to break Bhoys hearts. On Wednesday, though, it was the Hoops ending on top in an identical scoreline- a fairytale for Celtic, but a familiar story for Barca.

The Catalans' last European defeat had also come on British soil, a 1-0 reverse at Stamford Bridge in the semi-final first leg last season, which was followed by a disappointing draw in the return which saw the holders eliminated in Pep Guardiola's final Champions League clash as coach. Lionel Messi missed a penalty in the second match and was strangely subdued in the first meeting in London as the Blues defended deeply, put men around him and squeezed the spaces. Barca, without the injured David Villa and devoid of imagination as their top talent toiled, lacked a Plan B. And on Wednesday night's evidence, they still do.

One common criticism of Guardiola's brilliant Barca side was the absence of an attacking alternative when things were not going his side's way. The signings of Alexis Sanchez and Cesc Fabregas were supposed to offer the Catalans a new dimension in tricky fixtures like last night, but the problems remain.

A gradual change in tactics last year and even more so this term under Vilanova has seen Barca adopt a more direct style, particularly away from home. Players have been instructed to ship the ball forward more quickly, to use the width of the pitch, shoot from distance and deliver long corners instead of short ones. For the sake of efficiency, some of the pretty passing has gone.

Results have been mostly positive. Only one loss (to Madrid in the Spanish Supercopa), one draw (against the same opponents in La Liga), and 14 wins in their other games have been testament to that.

Tito's team have struggled defensively at times, however, with a number of key absences, and were fortunate to avoid defeat against a Sevilla side who had harried and pressed them superbly until Gary Medel's dismissal allowed a Catalan comeback in the dying minutes and Barca won 3-2 in September at the Sanchez Pizjuan. And on Wednesday, their luck ran out. One set piece, with Alba beaten in the air by Victor Wanyama, and Tony Watt's second following a long punt forward by Fraser Forster, proved enough to undo the visitors before Messi's late consolation which, in the end, was futile. The Argentine will have wished for a happier goal to dedicate to his new-born son Thiago, and finished on the losing side, after scoring, for the first time ever in the Champions League.

Messi tried harder than anyone to make things happen for Barca and came close as he rattled the bar with a long-range effort. Barca mixed it up when they could, with Alexis Sanchez also heading against a post, and several others shooting from distance.

Villa later came on, too, and Pedro had his moments, but still Barca lack the diversity they enjoyed in attack in Guardiola's first season, when Messi, Samuel Eto'o and Thierry were the front three - a trio with height, physicality and strength, as well as pace and fantastic finishing ability to go with it.

Even that side came within a whisker of a European exit at Chelsea before Andres Iniesta's last-minute strike in the semi-finals en route to the trophy 2008-09, while Barca were undone by an ultra-defensive, 10-man Inter at Camp Nou a year on in the last four, with Zlatan Ibrahimovic in their side, before last term's damaging defeat to the Blues.

The Catalans are now likely to face more similar systems later in the competition and somehow, perhaps by restoring Villa, moving Messi or even a change in system, Tito's team simply must find a way through the wall of defenders. If not, Wembley - scene of their 1992 and 2011 triumphs in this competition - may not be hosting another famous Blaugrana victory this time around.

It was a night Celtic fans will never forget. Beating Barcelona was an astonishing result for the Scottish Premier League champions and in the eyes of many; it was a match where a star was born in Victor Wanyama. anyama was magnificent against the Catalan giants, heading home the opening goal and producing a superb all-round midfield display, with his tough tackling, energy and smart distribution of the ball all coming to the fore.

For more casual observers, the two games against Barca in the last fortnight will have been the first time they have seen or noticed the Kenyan, but in truth he has been impressing ever since he first signed for Celtic for just £900,000 from Belgian side Beerschot AC in 2011.

Neil ennon’s side are desperate to tie him to a new contract, even with his current deal not due to expire until 2015, as they grow wary of interest from bigger clubs.

Premier League giants Arsenal and Manchester United are amongst the big guns who have scouted Wanyama and it is easy to understand, with their interest, why his agent is in no hurry to accept the Bhoys’ offer of fresh terms. If Arsene Wenger or Sir Alex Ferguson needed any further persuasion to firm up that initial interest with a concrete bid, they need look no further than his display against Barcelona, although if they have done their homework properly, his star display would not have come as a surprise.

In truth, Wanyama would be an ideal signing for Arsenal or United– representing exactly the type of player both clubs are currently lacking in their squads. he player may have had a £25 million price-tag slapped on his head by Lennon when the manager asked about a potential transfer, but in reality it is expected he would be allowed to leave for around half that figure.

Even though that is a few million pounds higher than it would have been before his and Celtic’s impressive Champions League campaign began, it still represents impressive value.

Wanyama performs best as a central midfielder, although he is also capable of playing in the centre of defence. He is a huge physical presence and impressive athlete, excelling in breaking up play, strong in the air and often representing the heartbeat of his side in midfield.

But he is not just a strong defensive midfielder. The Celtic man can play too, which is what makes him appear destined to reach the very top. His passing skills are good– he rarely loses the ball- and he possesses a lethal long-range shot. It may seem rash comparing him to a player who is as complete and as decorated as Yaya Toure, but there are similarities between the two and that is the type of level Wanyama is capable of reaching.

At just 21, he still has enormous room to grow further. There are still areas of his game he needs to improve– occasionally he can switch off defensively and he needs to get himself into better positions off the ball, but all the raw credentials of a top-level player are already in place. One of the players Wanyama outshined against Barcelona was Alex Song, a player Arsenal have yet to properly replace after selling in the summer.

The fact the Gunners are missing injury-prone Abou Diaby as a physical presence in their midfield highlights just how short they are of options in that area, and a young, affordable talent like the Kenyan seemingly fits in with Wenger’s transfer policy. Manchester United’s poor midfield has been their weakness for years. Arguably they have solved the problem of lacking creativity, with the likes of Shinji Kagawa, Tom Cleverley and Anderson now regulars at the club and with Paul Scholes back from retirement.

But they are still missing a midfield general- an all-round, all-action player to take the game by the scruff of the neck, who will not let them get overrun or outmanoeuvred in the middle third. It is the type of player they have arguably lacked since Roy Keane’s departure and a void Wanyama is capable of filling.

Wanyama’s brother– McDonald Mariga– has been a Champions League winner with Inter and based on the Celtic midfielder’s career so far it is hard to imagine him not achieving the same honour as his sibling at some point in the future. Celtic successfully rebuffed bids from QPR in the last transfer window, but you sense it will be a lot harder for them next time around when the bigger clubs come calling.

Ex-United full-back and Sky Sports pundit Gary Neville summed that up, saying after the match: "That wasn’t the performance of a 21-year-old. That display has put him right in the shop window and Celtic will do very well to hold on to him."

Celtic will be desperate to keep their star man for the time being, particularly as they look to progress further in the Champions League. He is a key player who is under contract for another three years, which puts them in a strong bargaining position. Deep down though, they will know that eventually Wanyama will be moving on and if Arsenal or Manchester United are not at the front of the queue, they will be making a big mistake.

Manager Neil Lennon brushed aside praise aimed in his direction following Celtic's magnificent if unexpected Champions League victory over Barcelona. Tactics, he said, mean nothing. The players are all that matters. But, with respect to the man whose side had just inflicted defeat upon Barcelona for the first time this season (outside the Spanish Super Cup), he was talking nonsense.

For Lennon has to take enormous credit for ensuring every player he sent out onto that pitch defied a technically superior opponent to record one of the outstanding results by a Scottish club in Europe. Bear in mind that this Barcelona team has started the domestic season better than any previous Barca side.

They may be a shade less impressive than Pep Guardiola's Champions League-winning team, but they had already equalled Guardiola's best start to a European campaign and look good to reclaim their La Liga title from Real Madrid.

So, when the pre-match team news confirmed that the Celtic captain Scott Brown had succumbed to a virus and their predatory striker Gary Hooper was not fit enough even to make the bench, with James Forrest and Emilio Izaguirre already ruled out, the portents were not good for the masses streaming into Celtic Park.

But, just as he had in Camp Nou two weeks before, Lennon sent out a well-drilled 4-4-1-1 formation designed to limit Barcelona's chances, but also to try to mount a threat of their own.

The first of those aims was, on the whole, achieved, with Kris Commons typifying the all-hands-to-the-pump resolve as he constantly tracked back to help more naturally defensive-minded colleagues to harass and harry the ever-patient Barcelona stars.

Joe Ledley probably touched the ball fewer times than in any other match he has played and yet his shuttling around the pitch, denying players space, made his contribution priceless.

Barcelona appeared at times over-elaborate, but the truth was that their traditional give-and-go football just wasn't creating the spaces it usually does. And, when it did, Fraser Forster was there to further enhance his growing reputation as a top-class goalkeeper.

At the other end of the field, Miku produced arguably his best performance since joining Celtic as he dropped off the front to pick up the ball and start rare forays forward. But Celtic's best chance of a goal was always going to be from a set-piece and so it proved with the opener. Lennon had pin-pointed this, but correctly stated that without the accuracy of Charlie Mulgrew in these situations, the chances would have been worthless.

Celtic have come a long way since their last Champions League match at home. Unlike that night against Benfica, they now look confident in their ability to compete at this level. That confidence, from the two matches against 'the best team in the world' as well as the hugely important win in Moscow, should now allow them to secure a place in the last 16. They can go to Lisbon in two weeks with the belief they can come away with a point at least.

Celtic are a team growing in stature and, despite his modesty, Neil Lennon is a manager doing likewise. Yes, the Glasgow giants have won the European Cup before but Wednesday night’s 2-1 win over Barcelona, containing players widely acknowledged as one of the best groups of all-time, has to rank right alongside their greatest-ever triumphs.

Two weeks ago it looked like Neil Lennon’s side had heartbreakingly missed the opportunity to make their mark against the Camp Nou stars when they were pegged back after taking an early lead and conceded a last-gasp winning goal to Jordi Alba.

On Wednesday night though, the tables were turned. This time, Alba was on losing end of a key personal duel when Victor Wanyama powered above him to head home a first-half opener. It seemed inevitable that the pain of two weeks ago was going to repeat itself as Barca’s magicians continued to dominate possession, hitting the woodwork twice in the opening 45 minutes and forcing the brilliant Fraser Forster into a number of key saves.

After the break the pattern was unchanged but the hosts continued to hold firm and with every passing minute the belief began to grow– the impossible dream really could happen. Then it was ecstasy with seven minutes to go when Xavi failed to deal with a long clearance and youngster Tony Watt ran on to produce a remarkably composed finish past Victor Valdes. That it was Watt who scored the decisive goal summed up the gulf in class between the two sides and the magnitude of Celtic’s achievement.

The 18-year-old- barely recognised by football fans outside of Scotland- was playing in the Scottish Second Division with Airdrie United just over a year ago, yet he capitalised on a mistake from one of world football’s greats. Even then the euphoric feeling wasn’t to last for long on an unbelievable evening. Lionel Messi struck in the 91st minute to ensure Celtic fans would be made to suffer right up until the final whistle.

The end to the game finally arrived after an agonising four minutes of injury time and even the joyous scenes on the pitch were overshadowed by stunning celebrations around the famous Celtic Park stadium. From Neil Lennon jumping on his exhausted players, to Rod Stewart bursting into tears as he watched from the stands, this is a night nobody connected with Celtic will ever forget.

On a day that started on a sour note when Hearts were issued with a winding-up order over an unpaid tax bill, the unbelievable victory for Celtic summed up the ups and downs of Scottish football.

But there have been few highs that are as sweet as this. Lennon and his players have secured their own place in history and who is to say how far they can now go. They have beaten Barcelona and no team will fancy a trip to a Glasgow, facing the club’s deafening supporters as well as the brave players on the pitch, if the Hoops are to take their place in the knock-out stages.

Messi, Xavi, Andres Iniesta & Co. are legends of the game but in the likes of Forster, Wanyama and Watt, Celtic fans have their own heroes. Man for man, nobody in green and white let themselves down and the plaudits coming their way in the days, months and years ahead will be thoroughly deserved.

Celtic have beaten Barcelona. It is a result that may never sink in properly. The side who have won two of the last four Champions Leagues came and saw but were conquered. The success must be enjoyed and has to be savoured because even in another 125 years, it will be hard for the Celtic to achieve a feat as great as this again.

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