IT has been well documented over the years how the appointment of Jock Stein as Celtic manager in 1965 was instrumental to the success the Glasgow club subsequently enjoyed in the European Cup.

All but one – striker Willie Wallace - of the players who would become known as the Lisbon Lions following their historic 2-1 win over Inter Milan in 1967 were already at the club when Stein took charge.

The Scot brought an ambition, organisation, professionalism and tactical wherewithal which had been previously lacking and which brought out the very best in the hugely talented squad he inherited.

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But just how much did Celtic’s first encounter with Barcelona in the second round of the Inter-Cities Fairs Cup in 1964 have to do with the achievement which Celtic later savoured?

According to Bobby Lennox, who featured in the second leg of the double header against the Catalan giants, a great deal.

Celtic lost their initial meeting with Barca on Wednesday, November 18, 1964, in the Nou Camp 3-1 after Jose Antonio Zaldua, Juan Seminario and Joaquim Rife had all netted for the home team and John Hughes bagged a consolation goal for the visitors.

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The rematch in front of a crowd of 43,000 at Parkhead a fortnight later was closer, in terms of the scoreline at least, and finished 0-0 at the end of 90 minutes.

Yet, Lennox, who was just 21 at the time and had made only a handful of first team appearances, recalls a team which included Ronnie Simpson, Tommy Gemmell, Bobby Murdoch, Billy McNeill, Jimmy Johnstone and Stevie Chalmers, all future Lions, being comfortably second best.

Writing in the Glasgow Herald the following day, Raymond Jacobs was certainly of the view that Celtic had been outclassed by vastly superior adversaries.

“At scarcely any moment did Celtic look capable of retrieving the deficit of two goals which they inherited from the first leg,” he opined. “Barcelona had speed on the ground, speed in the air, and, above all, speed between the ears.

“Theirs was a style of football too sophisticated for Celtic either to understand or to match. Kocsis, the great Hungarian of former days, has probably forgotten more about the game than Celtic’s players know.”

Lennox, now 73 and happily retired in his native Ayrshire, recalls Sandor Kocsis and his team mates being exceptional, but it is Julio Cesar Benitez who left a lasting impression.

“I played against a Uruguayan called Benitez who was the best player I ever came up against,” he said. “I played outside left that night and he was their right back. He made my life very difficult indeed that night. He was quick, strong and a good all-round player.

“He died quite young that lad (Benitez passed away aged just 27 before a Real Madrid game in 1968 after eating contaminated seafood) which was a terrible shame. He was an absolutely terrific player.”

Lennox feels that defeat to the Barcelona side which had won the Inter-Cities Fairs Cup, a now defunct competition which ran from 1955 to 1971, twice in the previous nine years underlined to Celtic the heights they had to scale individually and collectively to prevail in Europe.

“I hadn’t been involved in the away leg,” he said. “I was in and out of the team at that time. I travelled with the team to Barcelona, but I wasn’t picked. There were no substitutes at that time. You were either on the park or in the stand so I sat and watched.

“Ronnie Simpson made his debut that night and was great. They were just a brilliant side. Kocsis was absolutely terrific as well. He was a member of the great Hungary team of that era and was a tremendous forward.

“The return leg was one of my first games in Europe and we weren’t a very experienced team. It was an eye-opening experience for all of us. I think it made us realise the level that we had to get to and how well we had to play to be a success in Europe. They were a really good team. They were far better than us.

“It was an invaluable learning experience for us all. I think it made us all realise that we had a long way to go and a long road in front of us.

“Mr McGrory was the manager in that Barcelona game. Everything changed for us in Europe when Jock came in. Training, tactics, preparation, everything changed. We started training with the ball all the time. We still did a lot of running and worked hard, but we had the ball all the time.”

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Lennox works in the hospitality suites at Celtic Park on match days and is looking forward to attending the Champions League game between the Scottish champions and their Spanish rivals on Wednesday evening.

He appreciates that Brendan Rodgers’s side has little chance of overcoming Luis Enrique’s team, as was the case when the two clubs first met 52 years ago, but feels they have a chance of causing an upset with the backing they are sure to receive.

“Celtic have done very well this season,” he said. “Brendan has made a big difference. They have been good to watch and always look like they can score a lot of goals no matter who he plays. Both (Moussa) Dembele and (Leigh) Griffiths look like they can score whenever they take to the pitch.

“I meet all the boys at these games. It’s great. All our goals are from much further out. It is always a great night in these sort of big games. At Celtic Park we have got a chance no matter who we are playing.”