The danger is always of overreacting. We’ve seen Manchester City have a blip at this stage of the season before. But still, defeat to Brighton on Saturday means that, for the first time in his career as a manager, Pep Guardiola has lost four successive games. It would be extremely premature to suggest the empire is crumbling but, equally, for the first time in a long time there is a sense that City’s aura may be beginning to wane.

But first, some context. One defeat was in the Carabao Cup and another was in the Champions League, where City sit 10th in the table; even if they do miss out on the top eight who go through to the last 16 automatically – they have Feyenoord (home), Juventus and Paris Saint-Germain (away) and Club Brugge (home) next – they will surely at the very least be in the play-offs. But two of the recent defeats were in the Premier League, away at Bournemouth and then Brighton, and as a result City sit five points behind Liverpool.

It’s not unusual for City to have a slight wobble at this stage of the season. Guardiola likes his teams to peak in March and April, when the critical games come around in Europe, which is why the characteristic pattern of City’s title successes is of them putting the burners on in the spring and either overhauling a challenger or pulling away from the pack. That means that occasionally they are not quite at their best in the autumn, and there’s perhaps also a sense now of Guardiola working out how best to deploy his resources, developing his tweaks and innovations for the season.

It was at just this point of last season that they had a rough patch, a run of six Premier League games in which their only victory was an unconvincing 2-1 win at Luton. After the last match of that run, a 2-2 draw at Crystal Palace, City had 34 points from 17 games. This season, they have 23 points from 11 games. Which is to say that the likelihood is that at the halfway mark of the Premier League season, 19 games, it’s entirely probable they will have roughly the 40 points they had last year. Perhaps Arne Slot’s Liverpool, who went five points clear with Saturday’s 2-0 win over Aston Villa, are more formidable rivals than Mikel Arteta’s Arsenal were – City’s visit to Anfield on 1 December should give a clearer indication – but in terms of their own numbers, there is no reason for City to panic.

Nor have the performances been terrible. City were the better side in the first half against Sporting and Brighton and could easily have been a couple of goals up at the break in each. On another day their late surges against Bournemouth and Tottenham would have brought equalisers. But the point is that suddenly they look vulnerable.

Guardiola has been around long enough that the flaws in his sides have become familiar. He favours a high line that means if the press goes awry his teams can often be undone by simple balls in behind the defensive line. That’s why he spends so much time focusing on control and on not giving the ball away in situations that could lead to a counter. And the press at the moment, perhaps largely because of the absence of Rodri, is not functioning perfectly. Injuries should never be an excuse – the very best sides don’t dwell on absences but find a way to deal with them – but it is perhaps an explanation. Injuries more generally have clearly played a part. Kevin De Bruyne is just returning, Rúben Dias and John Stones are missing at the back, and the absence of Jack Grealish, Jérémy Doku and Oscar Bobb has reduced their creativity.

When things go wrong for Guardiola sides, they have a tendency to concede goals in sudden bursts – as though the way players have to subjugate themselves to the demands of the system means there is nobody with the personality to step up and seize a game when that system is threatened. Against Sporting, two goals were conceded in three minutes; against Brighton it was two in five. Rodri, like Vincent Kompany before him, was perhaps leader enough to prevent that glitching of the mechanisms; in that aspect as well, he is missed.

But this side are also struggling in unfamiliar ways. Kyle Walker, whose pace has been such an asset over his career, suddenly looks, if not slow, then at least not what he was. It may be a fitness issue but, equally, it may just be that, at 34, age is beginning to sap him. And then there is the more general issue of fatigue, which Guardiola has begun to talk openly about. Almost all elite players are playing too much, but perhaps they feel it more when they have already achieved so much. Maintaining the hunger is one of the great challenges for successful managers. And who knows what impact the Premier League charges against City have had?

It was a run of two wins in seven games at this stage five years ago that gave the first clue City would cede the league title to Liverpool, but that is the only time Guardiola hasn’t found a way to come back. He may do so again but dragging City back from here may be his greatest challenge.

• This is an extract from Soccer with Jonathan Wilson, a weekly look from the Guardian US at the game in Europe and beyond. Subscribe for free here. Have a question for Jonathan? Email [email protected], and he’ll answer the best in a future edition