What had seemed like a routine win for Chelsea became something a lot more mysterious thanks to a cryptic comment from Enzo Maresca in the post-match press conference. “The last 48 hours,” he said, “have been the hardest since I joined the club because so many people didn’t support me and the team.”

But which people? It was far from obvious. There was a clear sense Maresca was directing a message to somebody: he made the statement in response to a question about Malo Gusto’s form and repeated it before clarifying: “I love the fans and we are very happy with the fans.” Nor did it seem that he meant the media; he has never previously given any indication he cares what journalists and pundits say, there was no sense of hostility and he had appeared in perfectly good spirits at his pre-match press conference.

Given he accepted the blame – again, without being pressed on the issue – for the defeat at Leeds, saying he had got the team selection wrong, the implication was that somebody within the club has challenged or in some other way annoyed Maresca since the Atalanta defeat. The issue, though, is far from clear; asked if he was talking about some “internal” problem, Maresca replied “in general”.

After three games without a win, this was a much-needed victory but it was one that highlighted the oddity of Maresca’s side. They have a squad packed with extraordinary talent, and are capable of passages of exceptional football, but they are also wildly inconsistent, even within individual games.

They won easily, could have won more easily, and yet also had spells in which the game threatened to slip from their grasp. Every time it looks like everything might be coalescing into something coherent, perhaps even title-challenging, they stumble, and every time it looks like a blip might become a crisis, they embark on a run of positive form.

When Chelsea drew against Arsenal two weeks ago, despite being reduced to 10 men before half-time, it meant they had lost just one in 12 in all competitions and it was possible to see them taking advantage if Arsenal faltered. Since then, though, they have lost to Leeds and Atalanta and been held to a draw at Bournemouth. They began the weekend fifth, eight points off the top, and are 13th in the Champions League table. Perhaps that level of inconsistency is inevitable with a squad so young; which is where it’s worth remembering that their youth is a policy based not in economic necessity but through a conscious policy of regarding players as assets to be spun and sold at profit.

The loss of Moisés Caicedo, suspended for three league games after that red card against Arsenal, obviously has not helped, but he was available against Atalanta and couldn’t maintain second-half control.

Injuries at the back have not helped, with Levi Colwill suffering an anterior cruciate ligament injury in August. Although Wesley Fofana is back after missing four games through concussion, Maresca is reluctant to risk playing him more than once a week. The difference when he plays is stark: one defeat in 10 when Fofana has started this season, five defeats in 14 when he has not. Chelsea have not conceded more than once with him on the pitch in any game this season. It is not that Trevoh Chalobah, Tosin Adarabioyo or Josh Acheampong aren’t up to it; more that they benefit from having an experienced head alongside them. Thiago Silva, arguably, has never properly been replaced.

Cole Palmer, making his first appearance at Stamford Bridge since the opening weekend of the season, got his first goal in almost three months as he latched on to Gusto’s through-ball to put Chelsea ahead in the 21st minute. Gusto added a second, turning in a cut-back from Pedro Neto, just before half-time.

Without ever really looking like they would get back into the game, Everton had their chances, and Iliman Ndiaye rolled an effort against the post late on.

“I’m disappointed because we didn’t win, and disappointed because we got a couple of injuries but not disappointed with how we played,” said David Moyes. “Maybe we just ran short of the quality needed when we got the chances.”

If one chance had been taken, the mood might have changed and it might have been a different story. But that’s the nature of this Chelsea: for all their glitter, for all they are capable of challenging the very best, there is a brittleness to them. And that, ultimately, will probably prevent them winning the very biggest titles.