Millwall could well cause an upset against Tottenham on Sunday – that's if the history of London cup derbies is anything to go by.
The 13 London-based clubs who play in the top four divisions of English football have faced one another 94 times in the FA Cup since the Football League was expanded to four divisions in 1958.
As many as 60 of those FA Cup London derbies were between teams who went on to finish 20 or more places apart in the football pyramid at the end of the season, or are currently separated by more than 20 places in the cases of this season’s cup derbies.
And 37 of those 60 matches (62%) saw the team who finished higher in the league win the game.
The underdogs have held out for a draw 17 times – winning one on penalties – and have won outright six times.
But it’s Millwall who are the kings of the London FA Cup derby upset.
The Bermondsey club are responsible for eight of the 23 matches where the higher ranked team didn’t win – that’s more than by any other club.
Their biggest upset came in 1965 with a Third Round 2-0 victory over Fulham, who went on to finish the season 50 league places above the Lions.
Two seasons later Millwall held out for a draw against Tottenham, who went on to finish 27 places above them.
Millwall were drawn against Chelsea in the Fourth Round in 1985. The Lions won the match 3-2 despite 40 league places eventually separating the two sides by the end of the season.
In 1995 Millwall held out for a draw against Arsenal and then won the replay 2-0 against a side who finished 22 places above them.
Millwall drew Chelsea in the next round. The west London side finished 23 places above Millwall that season but the Lions held out for a draw to force a replay which they then drew and went on to win on penalties.