Rivals often present themselves as polar opposites but Arsenal and Tottenham Hotspur have rather more in common than they would care to admit. Some four miles apart, they are neighbours in more ways than one.
They are separated by one point and one place in the English Premier League table.
Teams that sit side by side have encountered the same problems, from losing leads to encountering defeat rather more often than they would have intended. It is three losses in four league games for Spurs, three in six for Arsenal.
Teams who were being praised in September risk being branded underachievers in November.
Now each is starting to miss a Dutchman they sold in the summer; Robin van Persie and Rafael van der Vaart, who left London to rather less fanfare than his compatriot, but whose significance is becoming more apparent.
Not least in this fixture. Van der Vaart was their derby standout, scoring four times in as many meetings with Arsenal, including one in the November 2010 victory at the Emirates Stadium, Tottenham's first triumph on enemy territory since 1993.
A second appeared on the cards in February when the former Gunner Emmanuel Adebayor put Tottenham 2-0 ahead. And it is here that Arsenal and Spurs' paths diverge dramatically.
Inspired by Van Persie and Theo Walcott, Arsenal surged back to win 5-2.
It was part of a run that enabled them to overhaul Tottenham in the table and, together with Chelsea's Champions League triumph, deny Spurs a place in Europe's premier club competition.
So Andre Villas-Boas may owe his position at White Hart Lane to that Arsenal revival.
He is Tottenham's 10th manager in Arsene Wenger's long reign across North London and aiming to become the first to finish above the Frenchman.
That may not mean as much if the bar has been lowered. "It's obvious that Man United, Man City and Chelsea are into a big running towards the title," Villas-Boas said. These two sides are not.
"Both teams are not where they have to be," the Portuguese added.
Tottenham kick off in seventh and Arsenal eighth, both aiming for fourth.
Villas-Boas was not appointed to pilot Spurs to the upper reaches of mid-table, just as Wenger’s speciality has been taking Arsenal into the top four, not the top eight.
Consistency has been his forte, just as this has been the most reliably eventful derby.
The last 10 meetings have produced 46 goals, with scorelines veering from 5-1 to Tottenham to 5-2 in Arsenal's favour via 3-3 and 4-4 draws. "The quality of the game has been very good," said Wenger, a connoisseur of the classic.
Factor in a typically fragile Arsenal defence and it has the makings of another entertaining affair. In their past two games, Arsenal have gone two ahead of Schalke and Fulham and beaten neither. When they have encountered elite opposition, Tottenham have led Chelsea and City and lost to both.
There could be as many subplots as goals: the returns of Adebayor and William Gallas, neither exactly beloved by the Arsenal faithful, to the Emirates Stadium; the quests for redemption of the vice-captain Mikel Arteta, who missed the penalty that would have secured three points against Fulham, and the captain Thomas Vermaelen, who has struggled of late; a belated first home derby for Jack Wilshere, Arsenal's next great hope.
There are the differing fortunes of Arsenal's summer signings, the initially superb but then slumping Santi Cazorla and the fast improving Olivier Giroud, and their Tottenham counterparts.
Clint Dempsey has faded since his winner at Old Trafford but Jan Vertonghen, who attracted Wenger's interest, could make Arsenal envious.
And, inevitably, there will be the scrutiny of the Tottenham manager's every move. He benched his top scorer, Jermain Defoe, at City and continues to keep France's first-choice goalkeeper Hugo Lloris in reserve.
For an idiosyncratic decision maker like Villas-Boas and a man whose ethos is increasingly under attack such as Wenger, victory would bring vindication but derby defeat would be diabolical.
These are enemies with distinct similarities.
Follow us @SprtNationalUAE