There is opportunity in a rivalry. When Arsenal met Tottenham, the prize used to be the status as the pride of North London.
Now, Chelsea's collapse elsewhere in the capital means both can look to fill a void Jose Mourinho's declining champions have created.
Spurs can spy a top-four place.
Arsenal can eye the title.
But each can spot a sizeable obstacle nearby.
Quietly, Tottenham have fashioned the longest unbeaten run in the Premier League, even if half of those 10 games have been drawn.
Arsenal have reeled off five consecutive top-flight victories, scoring 16 goals.
Spurs have bagged 14 in the same time, yet these sides have two of the best defensive records in England.
Something has to give.
Their meetings have produced 101 goals in 11 seasons but this could be low-scoring.
It is a test of new-found resilience, particularly Tottenham's, and powers of recovery, especially Arsenal's after Bayern Munich thrashed them 5-1. This is an examination if their squad have the required strength in depth.
One flank will consist of understudies, second-choice right-back Mathieu Debuchy and Joel Campbell, who seems their seventh-choice right winger but scored at Swansea last week.
Olivier Giroud lost his place to Theo Walcott but is now renascent while the Englishman is injured.
Yet, if Arsenal are reliant on reserves, they are aided by the excellence of the pivotal performers.
Santi Cazorla has been consistently influential. Alexis Sanchez has exploded into form.
Mesut Oezil's outstanding October, including goals against Manchester United and Bayern, represented his best month as a Gunner.
If Arsene Wenger has found different ways to win, with and without the ball, Mauricio Pochettino's plan against talented teams can be reduced to two words: Outrun them. Spurs have covered more distance than their opponents in 10 of their 11 games this season.
Tottenham overwhelmed the last title contenders they faced, Manchester City, in a 4-1 win.
In the classy Christian Eriksen and rejuvenated pair of Mousa Dembele and Erik Lamela, they have allied flair with energy.
Yet, while City were overcome at White Hart Lane, Spurs have won only once at Arsenal since 1993.
They have already lost once to the Gunners this season, when Mathieu Flamini's rare double secured a 2-1 triumph in the League Cup, and this is the truest test of Pochettino's reconfigured defensive structure.
The Belgian pair of Jan Vertonghen and Toby Alderweireld may be Spurs' best centre-back partnership for years.
But Spurs have never kept a clean sheet at the Emirates Stadium and Pochettino is Tottenham's 12th manager during Wenger's never- ending reign at Arsenal.
They have been separated by a gulf in class for much of that time.
If that is closing, as ever when they cross North London, Tottenham are the outsiders.
ARSENAL v TOTTENHAM
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