Those of a Chelsea persuasion will undoubtedly know the events of the 2-2 draw at Wembley and the 2-1 victory for the Blues that followed in the replay at Old Trafford. Legends were created across 240 minutes of intense – and at times brutal – action as our first FA Cup triumph was secured.

Yet did you know the home shirt Chelsea wore at Wembley was not the same as the home shirt donned at Old Trafford 18 days later? The story behind why is recounted in Blue Is The Colour - The Official History of the Chelsea Shirt. Author Nik Yeomans, with accompanying imagery from the soon-to-be-released book, sets the scene...

'Upon reaching the 1970 FA Cup final, Chelsea won the coin toss which designated the home team and elected to wear their full home kit, including white socks.

'In 1967 they had also won the toss before the final against Spurs but the FA had requested they wear blue socks so that Spurs could wear all-white. With the memory of that disappointing defeat, the Blues stuck to their guns on this occasion and their opponents, Leeds United, elected to wear the red socks from their away kit with their traditional all-white home shirts and shorts.

'For the first time in the club's history, the shirts used for the final included specific embroidery for this one-off match, with the worlds WEMBLEY 1970' appearing within a scroll beneath the club crest.'

The match itself was not one for the purists; a dreadful pitch was part of the reason as to why. Peter Houseman and Ian Hutchinson, whose match-worn shirt is pictured above, netted for the Blues. Jack Charlton and Mick Jones struck for the Whites.

Such was the state of the Wembley pitch that the FA decided the replay would be held at Old Trafford. Chelsea were the 'away team' for the fixture and after Leeds opted to wear their traditional all-white home strip, the Blues needed an alternative to their usual home kit.

Yeomans continues the story: 'The decision was made to play the replay in the yellow socks of the away kit. And because of the prestige of the occasion, it was also decided that to complete the look that would be seen by a live television audience of millions, the players would also wear jerseys with a yellow club crest and shorts with a yellow stripe and numbers.

'It is not known whether the inspiration for these relatively small but highly significant alterations to the Chelsea kit originated from within the club or from kit manufacturers Umbro. However, it was an inspired choice, and the result is one of the most iconic kits the club has ever worn.'

In front of a UK television audience of 28.6 million – second only to the 1966 World Cup final for a sports broadcast and sixth in general – the Blues battled their way to a 2-1 victory. Peter Osgood levelled the contest in the 78th minute and in extra time, David Webb headed home at the back post to secure our first-ever FA Cup triumph.

The Chelsea shirts worn that day inevitably became collector's items, even more so given how few were produced for the occasion, as explained in Blue Is The Colour - The Official History of the Chelsea Shirt.

'With just over two weeks between the first match and the replay, it is believed only 11 sets of outfield shirts and 12 sets of shorts were manufactured by Umbro (goalkeeper Peter Bonetti wore the same green shirt in both matches), which makes the jersey featured (above) incredibly historic and extremely valuable.

'It was worn by John Dempsey but he, like many of the Chelsea players, swapped with an opponent, in this case Paul Madeley, after the match. Dempsey had already loaned Madeley's Leeds shirt to the Chelsea FC Museum, and then in January 2023 the club acquired his match-worn shirt for the club archive.

'Also on display are the winners' medals won by skipper Ron Harris, goalkeeper Peter Bonetti, Ian Hutchinson and Peter Houseman.

'Following the FA Cup triumph, this combination became the default choice for the next two seasons whenever a change of socks was required. The same shirt design was worn in the European Cup Winners Cup games against Real Madrid in 1971, only on this occasion with plain yellow socks.'

In 2020, to mark the 50th anniversary of our first FA Cup final win, Nike created an immaculate modern version of the classic 1970 strip. It was worn in the third-round FA Cup victory over Nottingham Forest at Stamford Bridge.

Blue is the Colour is researched and written by Nik Yeomans, the foremost expert on the Chelsea kit over the years. Whether you are also an aficionado, a collecting enthusiast or a fan who simply wants to know more about this fundamental part of the club’s heritage, this book is simply a must-have.

It can be pre-ordered here now and will soon be on sale in-store and online.