Two more devastating set-pieces powered Arsenal to a 2-1 victory over 10-man Chelsea at Emirates Stadium, re-establishing their five-point cushion at the top of the Premier League.
With Manchester City having trimmed the gap to two points after beating Leeds, the pressure was on Mikel Arteta’s side.
In a tight, chance-light opening, Arsenal once again turned to their most reliable weapon - the corner.
The breakthrough arrived in the 21st minute.
Gabriel Magalhaes met Bukayo Saka’s delivery and headed back across goal for defensive partner William Saliba.
His effort struck Mamadou Sarr on the arm before crossing the line.
Chelsea responded positively and equalised before the break - also from a corner.
Reece James’ pinpoint cross was flicked on by Piero Hincapie, diverting into his own net to level the contest.
The visitors began the second half brightly and unsettled the home crowd, but Arsenal’s mastery from dead balls proved decisive again.
In the 66th minute, Jurrien Timber rose to head home Declan Rice’s corner - Arsenal’s 16th league goal from such situations this season.
Chelsea’s task became harder with 20 minutes remaining.
Substitute Gabriel Martinelli burst forward on the counter and was cynically brought down by Pedro Neto, who received a second yellow card and was dismissed.
There was late drama when Liam Delap bundled home what appeared to be an equaliser, but the goal was ruled out after Joao Pedro was adjudged offside in the build-up.
The result lifts Arsenal to 64 points, five clear of Manchester City, albeit having played a game more.
Opponents know it is coming - yet still struggle to prevent it.
Arsenal’s set-piece excellence continues to define their title challenge.
The Gunners have now scored 16 Premier League goals from corners this season, equalling the competition record for a single campaign.
Nine times they have taken a 1-0 lead via a corner - a testament to the precision and rehearsal behind their routines.
This was not a vintage Arsenal display.
Chelsea enjoyed spells of control, and David Raya was required to make key saves.
But potential champions win even when rhythm deserts them, and Arteta’s men once again found a way.
With memories of their last league title in 2004 still vivid for supporters, the resilience shown here suggests they are equipped for the pressures of the run-in.
Chelsea’s progress under Liam Rosenior has been undermined by recurring lapses in discipline.
Pedro Neto’s dismissal was their seventh red card in the league this season - and ninth in all competitions - leaving them perilously close to unwanted records.
The sending-off shifted momentum firmly back toward Arsenal at a moment when Chelsea had looked capable of taking something.
Defensive vulnerability from corners remains a glaring weakness.
While James’ deliveries caused problems at one end, the same old fragility at the other continues to haunt the youngest squad in the division.
With ground lost on rivals Manchester United and Liverpool, and key players facing suspension or injury concerns, Chelsea’s ambitions of a return to the Champions League require swift improvement.
At the Emirates, once again, fine margins - and familiar flaws - proved decisive.
