As a result of Stuart Armstrong’s equalizer against Southampton on Sunday, Arsenal lost points for just the second time this year and were forced to settle for a 1-1 draw.
Granit Xhaka’s goal in the opening period at St Mary’s gave Mikel Arteta’s team the lead.
After the break, though, Armstrong equalized, and Arsenal suffered for their missed opportunities to extend their lead.
The Gunners had won nine out of their previous 10 league games this season, with their lone loss coming at Manchester United. It was a rare lapse on their part.
The end of Arsenal’s eight-game winning run in all competitions leaves them two points clear of second-placed Manchester City with both having played 11 games.
While Arteta will be angry that Swiss midfielder Xhaka gave Arsenal the advantage and it wasn’t built upon, it is a testament to his team’s remarkable climb this season that failing to earn all three points qualifies as a disappointment.
As they pursue their first title since 2004, Arsenal has already established themselves as a serious contender, and they got off to a strong start on the south coast.
Bukayo Saka’s cross was inches away from Gabriel Magalhaes before Gabriel Martinelli caused havoc in the Southampton defence with a direct run that ended with Xhaka’s powerful drive repelled by Gavin Bazunu.
Xhaka turned provider moments later when he teed up Martin Odegaard for a low strike that whistled wide from the edge of the area.
Arsenal were in complete control and Xhaka delivered the goal their pressure merited in the 11th minute.
It was a smooth move as Saka’s backheel sent Ben White away down the right flank and his cross reached Xhaka, who crashed a blistering strike into the roof of the net from 12 yards.
Arsenal had never lost when Xhaka scored, a sequence stretching to 17 games.
Gabriel Jesus was inches away from doubling Arsenal’s lead when he shot into the side-netting from Odegaard’s pass.
Bazunu left Jesus frustrated again just before half-time as the Brazilian reached Odegaard’s lofted pass for a volley that the Saints keeper blocked at point-blank range.
Mohamed Elyounoussi’s last-ditch tackle stopped Jesus in his tracks after the Arsenal striker sprinted clear on goal.
But, for all their territorial dominance, Arteta’s team couldn’t land the knockout blow and they were hit with a sucker punch in the 65th minute.
Elyounoussi slipped a clever reverse pass through the heart of the Arsenal defence and Armstrong timed his run perfectly to slot a composed finish past Aaron Ramsdale.
With Southampton suddenly in the ascendancy, Joe Aribo tested Ramsdale with a low shot and Romain Perraud swivelled to drill wide.
Odegaard thought he had won it in the 79th minute when the Dane smashed home from Kieran Tierney’s cross but the goal was disallowed because the ball had run out of play.