Altrincham win is one of FA Cup third round's greatest giant killings

The FA, the Institute for Mathematical Innovation and sport statistical analysts Opta have released the research to mark the competition's third round this weekend.

According to a complex calculation that takes into account information like league status, as well as the order and timing of goals in the game itself, there was a one in 4,376 chance of a win for non-league Altrincham against First Division Birmingham City in 1986.

The calculation (Image: FA / Institute of Mathematical Innovation).

This means it was more improbable than the chance of receiving a four-of-a-kind hand in poker. However, The Robins overcame the odds and came back from 1-0 down to defeat The Blues thanks to a Ronnie Ellis strike and an own goal past a young David Seaman.

Bill Waterson, the club's co-chairman, said "It was a memorable night for those of us who were there. Such was our reputation at the time, all the fans thought we had a real chance of winning it, but it was easier said than done.

"The result not only brings happy memories, but boosted the club and the community surrounding it immensely and it still stands as a brilliant example of why we enjoy the FA Cup and what it means to be a part of Altrincham."

Dr Adwaye Rambojun, who worked on the complex calculation with Professor Andreas Kyprianou at the Institute for Mathematical Innovation, added: "Altrincham’s result defies logic, but on any given day the unthinkable can happen.

"That’s the magic of the FA Cup and we have seen it time and again throughout the competition’s illustrious history."

The only wins more improbable than the The Robins' are those for Hereford United and Stevenage against Newcastle United, and a 4-2 win for Woking against West Bromwich Albion 30 years ago.

The latter is most improbable with around a one in 16 million chance, less likely than the chance of conceiving identical quadruplets.