The unusual fixture took place in 1965, when Helmut Schon saw two friendlies with Chelsea as the ideal preparations for his West Germany team, featuring star man and Bayern legend Franz Beckenbauer, ahead of the following year’s World Cup.

In hindsight, knowing that West Germany’s opponents in the final of the 1966 World Cup turned out to be England, assisting their preparations may seem unpatriotic. However, that was of little concern to Chelsea’s outspoken manager and fiercely proud Scotsman Tommy Docherty.

After all, this is a man who listed beating West Ham on the opening day of the 1966/67 season, when Bobby Moore, Geoff Hurst and Martin Peters had paraded the World Cup trophy around the ground before kick-off, as one of his best moments as Chelsea manager. He even gave the Germans use of Stamford Bridge for training during the World Cup.

It was Docherty’s friendship with Schon and Wilfried Gerhardt, the head of the West German football association, that played a big part in setting up the two matches in ’65. Gerhardt, in particular, played a part in arranging several pre-season trips to Germany for the Blues in the Sixties, allowing us to pick up our new training gear direct from the factory before playing a few of the local sides.

Our exciting, young and creative style seemed to catch the eye in Germany, especially of Schon. In addition to giving his players plenty of room to improvise on the pitch, Docherty had taken ideas from all over the world when building his innovative ‘Doc’s Diamonds’ team, and that patchwork of international influences and unpredictability provided exactly the challenge Schon wanted to get his players ready for the World Cup.

The football world was smaller in those days. Long-distance overseas travel was still a rarity and footage of foreign matches almost non-existent. In Schon’s eyes, a game against Chelsea was the best substitute for taking on the teams of South America or Eastern Europe.

‘He said we weren’t like a British team,’ recalled Docherty. ‘He meant that we weren’t overly physical, that we played football from the goalkeeper outwards. The Germans loved it!’

‘At that time, the full-backs, Ken Shellito and Eddie McCreadie, were like outside-right and outside-left rather than right-back and left-back. You’d read in the paper that the Chelsea full-backs were offside all the time!’

It wasn’t just our Brazilian-style attacking full-backs which made us an appealing opponent either, although those who remember Ron Harris’ robust defending may feel Schon was playing with fire with his special request to his fellow manager.

‘They asked me if Chopper could mark Uwe Seeler because they felt when they played other national team, people would want to man-mark Seeler and they wanted a bit of practice at it. I said, “You’ve picked the right man in Chopper!”

‘Ronnie marked him the whole game. He didn’t do the things he would do in England, but he shadowed him everywhere. Seeler never got a kick.’

The appeal for Chelsea was obvious too. The same reasons that restricted Schon’s experience of playing against foreigners meant international teams were effectively an all-star XI for their domestic league. The chance for the Blues to see how they stacked up against such a high standard of opposition was impossible to resist.

The verdict was overwhelmingly positive. Harris did his job better than Schon could have anticipated as the West German attack was locked out in the first match in Duisburg in February. Barry Bridges’ late goal gave us a 1-0 win and plenty of admiration in Germany and back at home. One British newspaper ran with the rather gleeful headline ‘Chelsea whip the Germans!’ on their coverage of the game.

We clearly liked the challenge as we returned in August as part of a daunting pre-season schedule, in which we also took on a combined Celtic and Rangers team in Glasgow, as well as another exhibition team made up of AC Milan and Inter Milan’s best players.

Our trip to Essen between those two matches started even better than our previous game against West Germany, as Bridges picked up where he’d left off to open the scoring just eight minutes in, and Jim McCalliog doubled our lead before half-time.

The Germans had learned their lesson, though. After a double substitution during the break, the scores were level 20 minutes into the second half and one of those subs, Horst Szymaniak, gave them a 3-2 victory with an 87th minute penalty.

Much like that same West Germany team have never gotten over their suspicions surrounding the standard of officiating in the following year’s World Cup final against England, that late penalty awarded by a German referee seemed more than a little suspicious in sparing the hosts’ blushes.

Perhaps it is just as well, as if the decisions had panned out different at Wembley in 1966, Chelsea’s assistance in West Germany’s preparations might have got some of the blame for losing England the World Cup. As it was, we had defeated one World Cup finalist and then beaten the stars of the winners at West Ham, giving us a decent claim to being the best club team on the planet.