Manchester City's 15-match Premier League winning streak leading into Sunday's derby ensured that defeat to Manchester United is unlikely to put much of a dent into their hopes of a third title in four years.
City remain a comfortable 11 points clear at the top, and they could increase that gap to 14 with a win over Southampton on Wednesday.
Of course a serial winner like Pep Guardiola will not take anything for granted.
"In football, anything can happen, everything can happen," he said after the 2-0 defeat. "We can win the next games and lose the next games."
A look at reigning champions Liverpool and how their 68-match unbeaten run at Anfield has turned into six straight defeats shows the potential for things to fall apart spectacularly.
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But a first defeat in 29 matches to the current second-best team in England is hardly a portent for a similar disintegration.
However, the loss to Ole Gunnar Solskjaer's side did show that some holes in Guardiola's masterplan have not been quite completely sealed just yet - a fact that threatens to derail City's ultimate dream of winning the Champions League for the first time.
United's victory was predominantly built on the back of their threat on the break, something which has undone City in the past, with Solskjaer having now won on each of his three visits to the Etihad Stadium as United manager.
The Red Devils are well-drilled in soaking up pressure and have the speed in forwards Marcus Rashford, Anthony Martial and Daniel James to catch City on the break.
Being exposed in such a fashion has always been a danger with the way that Guardiola looks to defend with a high line, though it was something City were hoping they had overcome with the impressive form of centre-back pairing Ruben Dias and John Stones.
And while City must find a solution to that issue in order to see off domestic opponents, the best sides in Europe will be less cautious than United. They will back themselves to play City on the front foot, not allowing them to dominate possession and territory the way that Solskjaer's side tend to do.
What will be more concerning is the frantic opening 10 minutes which threatened to take the derby away from City before it had properly got going.
United were ahead inside two minutes when Bruno Fernandes converted from the penalty spot after Gabriel Jesus' clumsy challenge on Martial.
It could have been worse had Luke Shaw converted a glorious opportunity that was presented to him by Joao Cancelo in the fifth minute when the City full-back tried to dribble his way out of the penalty box.
The shell-shocked hosts lost all of their normal composure, with Dias, Rodri and Kevin De Bruyne guilty of playing stray passes as they were caught horribly cold.
Europe's best would have punished them further, and a repeat of such a frantic period could cost them heavily in the Champions League.
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Guardiola has so far failed to get beyond the quarter-finals with City, and often they have paid for similar crazy spells.
In his first season, they struggled to get to grips with Monaco in the opening half an hour of their last-16 second leg, conceding twice as they went out on away goals.
Liverpool scored three times in 20 minutes at Anfield a year later, Son Heung-min netted twice in three minutes in an away goals defeat to Tottenham in 2019 and Lyon also netted twice in eight minutes during last year's exit in Lisbon.
Guardiola has always insisted that the margins are slim in cup competitions, particularly the Champions League; one bad result and you are out.
City have often struggled to regain their control immediately after conceding and ties have had a way of running away from them.
They are certain to face testing periods if they are to have any chance of reaching the final in Istanbul in two months' time, and must find a way to quickly reset.
City were relentless in their record-breaking 21-match winning run. Sunday's defeat is a reminder that any let-up in concentration on the European stage could prove fatal.
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