Arsenal head coach Mikel Arteta lamented a "very unusual" characteristic of his side's performance in their gut-wrenching 3-2 loss to Manchester United in Sunday's Premier League showdown.
The Gunners suffered their first home defeat of the season in any competition against the Red Devils, whom they drew first blood against through a Lisandro Martinez own goal before chaos ensued.
Arteta's men reverted to their passive ways after going a goal up and deservedly fell behind to a Bryan Mbeumo finish and Patrick Dorgu thunderbolt, which triggered a quadruple substitution.
One of those changes paid dividends, as Mikel Merino bundled in an equaliser from a corner to seemingly rescue a point for the Gunners, but the Emirates was stunned into silence just three minutes later.
Another world-class goal - this time from Matheus Cunha - propelled Man Utd to a statement win in North London, where Arsenal conceded three times in one Premier League match for the first time since 2023.
While Arteta's side remain at the top of the rankings, they are now just four points clear of Manchester City and Aston Villa following victories for their title rivals at the weekend.
Arsenal 2-3 Man Utd: Mikel Arteta laments "very unusual" aspect of performance
Mbeumo's first goal came about from a Martin Zubimendi howler, and the Gunners then failed to stop two intricate Man Utd combinations before Dorgu and Cunha put away their long-range efforts.
Speaking to reporters in his post-game press conference, Arteta lamented the "very unusual" number of errors his side made on their own turf as their lead at the Premier League summit reduced to four points.
"Difficult to say. I think the first one probably leads to the second one, and the fact that you want to be more protective probably doesn't help to make those mistakes," the Spaniard said.
"There were three or four [mistakes], to be fair, very unusual today in the game. They are part of football and sometimes you get punished and sometimes not.
"Today we got punished and apart from that it has to be credit to the opponent for what they've done and in the manner that they managed to win the game."
Arsenal 2-3 Man Utd: Damning open play stat highlights Gunners struggles
Arsenal had failed to score in back-to-back Premier League draws with Liverpool and Nottingham Forest heading into Sunday's game, although they did put three past Inter Milan in the Champions League in midweek.
However, back in the top flight where teams defend deeper, Arteta's men so often do not have the answers, barring a slice of luck or set-piece mastery from dead-ball coach Nicolas Jover.
Of the 1.2 Expected Goals that Arsenal generated today, just 0.39 came from open play, compared to 0.81 from set-pieces; in contrast, Man Utd's 0.73 xG all came from open play.
Martin Odegaard and Bukayo Saka's creativity was stifled by Michael Carrick's side, but Arsenal arguably only had themselves to blame for apathetic, sluggish build-up play, which has been a theme of their season.
Not even a usually rock-solid defence could make up for a lack of invention and central penetration, and if the last 18 months are any indication, Arsenal's creativity issues will not be fixed quickly and could yet prove fatal in the title fight.