It always loomed large on Chelsea's calendar. A defining week has the potential to prove a decisive week. Just not, it seems, in the way their rivals had hoped.
Having negotiated a trip to Anfield, Chelsea have the chance to go 12 points clear at the top of the English Premier League when the final whistle blows today.
As they do not face potential champions again until April, they could have the simplest of paths to silverware.
If the title race would be best served by an Arsenal win, the Gunners now seem in a four-way fight for second place.
Whatever their objective, they would welcome a repeat of September's pyrotechnics. Arsenal were responsible for Antonio Conte's heaviest defeat as Blues manager, but the Italian's darkest day was also a new dawn. With his side 0-3 down after 55 minutes, he brought on left wing-back Marcos Alonso, switched to 3-4-2-1 formation and laid the seeds for a remarkable revival.
Chelsea's subsequent run has been based on tactical excellence and mental strength. They passed a test of nerves on Tuesday, drawing with Liverpool.
Arsenal had failed one, losing at home to Watford when the chance to close the gap on the leaders beckoned.
Typical Arsenal, perhaps. Losing at Stamford Bridge also conforms to the stereotype. They actually have three wins in their last eight visits but the four most recent have not even produced a point.
Arsenal have not scored on Chelsea's turf since January 2013 and the subsequent spell included a 6-0 thrashing in Arsene Wenger's 1,000th game in charge.
Now his side have to confound the form book, both in this fixture and this season.
The burden of proof, as ever, lies with Wenger. So do the difficult decisions. Conte could recall Pedro Rodriguez, who has four goals in four home games, or for Willian. Predicting his team is otherwise easy.
Wenger has more to ponder. Olivier Giroud has struck five times in seven outings but Arsenal look faster and more fluent without the Frenchman.
They have been slicker this season with Alexis Sanchez as the main centre-forward. Yet Lucas Perez also presents an enticing option, not least because playing Sanchez as a winger would pit him against Victor Moses. It would be the stiffest examination of the Nigerian's defensive credentials.
Wenger has to find a way to subdue Eden Hazard and Pedro or Willian when he is without four central midfielders. The onus may be shifted to attack because of necessity. He may regret the absence of the banned Granit Xhaka, who could have helped nullify the threat.
He may lament his own touchline ban, which will limit his ability to influence proceedings. But the hyperactive Conte should be a constant presence in the technical area, coaxing Chelsea closer to glory. A potentially damaging week for him could instead destroy his rivals' hopes.
CHELSEA V ARSENAL
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