Aston Villa moved to within two points of the Premier League summit as they continued their outstanding home form with victory over Arsenal.
The Gunners had led the table heading into the weekend but slipped to a 1-0 loss courtesy of captain John McGinn's seventh-minute strike - with Villa extending their winning home league run to 15 games in the process.
Arsenal twice had the ball in the net in the second half but Bukayo Saka was offside before Kai Havertz was denied a late equaliser having been penalised for handball.
Former Arsenal boss Unai Emery would have particularly enjoyed getting one over his successor - although Mikel Arteta watched on glumly from the directors' box as he served a one-match touchline ban.
Villa beat champions Manchester City here on Wednesday night and this success shows that they are legitimate challengers for the title this season.
Arsenal were disjointed for large periods of the game with Saka, in particular, struggling to make an impact on proceedings in a manner which he has become accustomed.
This season, Arsenal have often struggled to break down a low-block while largely enjoying themselves against sides who look to press.
Therefore, this was testament once again to the ruthlessness and guile with which Villa employ Emery's tactics and continue to befuddle some of the best teams in the land.
Saka had a good chance to open the scoring early on but, after drifting in unmarked at the back post he could not make meaningful contact on Gabriel Martinelli's swinging cross.
Villa would hit the front soon after, playing out from the back and not letting Arsenal get near the ball as Leon Bailey burst into plenty of space to break down the right before playing in McGinn, who had time to take a touch and turn before finishing emphatically past David Raya.
Having been so front-footed and driven in the win over City, there could have naturally been some drop-off less than three days later but the home side were running the show in the opening quarter of the game.
Martin Odegaard then shot into the side-netting as Arsenal at last began to string together some passes in the final third.
Martinelli was next up, beating the onrushing Emiliano Martinez to a ball over the top and looping a shot at goal that was cleared away by Diego Carlos.
With the visitors building up a head of steam, Odegaard had a fine chance to equalise but saw a shot from 12 yards out once again kept out by Martinez, who then saved from Gabriel Jesus before the break.
Arsenal saw calls for an early second-half penalty turned down after Douglas Luiz caught Jesus but a VAR check quickly came down on the side of the hosts.
Miscommunication in the Villa box almost gifted Arsenal their equaliser as Martinez looked to claim a corner but could only palm the ball into the back of Ollie Watkins, who was leaping to clear, and it hit the post before being collected.
Odegaard, who had arguably wasted Arsenal's best chance in the first half, then skewed a shot horribly wide as Villa's goal continued to live a charmed life.
Despite clearly tiring, Villa were still able to pose a threat themselves as a simple ball through the middle eventually saw half-time substitute Moussa Diaby picked out and he played in Lucas Digne, who shot low at Raya.
Saka then had the ball in the net only for the offside flag to bring an abrupt end to celebrations before Raya was again called upon to save from Watkins.
Havertz thought he had levelled in the last minute but referee Jarred Gillett awarded Villa a free-kick for handball against the German, with a lengthy VAR check ultimately siding with the on-pitch official.
