The good news for Arsenal is that they will start 2024 only two points off the league leaders Liverpool. The bad news is, well, just about everything else.

This was supposed to be the period that cemented their title aspirations; the crucial few weeks in which Mikel Arteta’s side built up a points haul to sustain them when winter turns to spring and the depth of their rivals’ squads is likely to have an increasingly important say in where the Premier League trophy ends up. Instead, it has exposed their biggest frailties and led to serious questions over how realistic their credentials actually are.

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Defeat here against a Fulham side that had lost their last three league games by an aggregate score of 8-0 meant a busy December that began with narrow victories over Wolves and Luton has concluded with just one win in the last six across all competitions. One new year’s resolution might be to forget that the past few weeks ever happened.

With his side looking worryingly toothless in attack as the season has worn on, Arteta opted to recall Eddie Nketiah in place of Gabriel Jesus for only his second league start since a brilliant hat-trick against Sheffield United. The impact of that change was nonexistent.

Nketiah was entirely anonymous, with the visitors hitting the target just three times all game and asking precious few questions of Bernd Leno. Those calls to sign another forward in January continue to mount with each passing match.

For Fulham, an odd rollercoaster ride continues. Marco Silva’s side bounced back from scoring just 10 goals in their opening 12 league fixtures by blasting 16 in the four games that followed before the recent barren run that coincided with Raúl Jiménez’s absence. The Mexico striker’s return saw him add yet another goal to his haul and, alongside Bobby De Cordova-Reid’s scrambled finish, helped to secure a comeback victory after Bukayo Saka’s early opener.

No one could deny that they deserved it. Calvin Bassey, on his 24th birthday, was superb at the heart of a Fulham defence that shut out almost everything thrown at it. On this kind of evidence they are not a side that should have the slightest concern for goings-on at relegation-threatened clubs beneath them.

Barely six weeks ago it would have been laughable to suggest Jiménez might ever become the unlikeliest of goalscoring talismans in this part of west London. Yet since a dismal run of 33 goalless Premier League appearances, he now unexpectedly has five in his last seven.

This one halted a Fulham run of three league games without a goal – during which Jiménez missed all but 22 minutes through suspension – and was one of his easier tasks thanks to a magnificent delivery from Tom Cairney, whose dangerous low ball travelled all the way across the six- yard box, allowing the forward to tap in at the far post.

That strike ensured the scoreline was all square at half-time after Arsenal had taken a lead just five minutes in with the kind of swift break that leaves opposition supporters wondering quite how it happened.

From David Raya’s roll-out to Kai Havertz, the ball was hastily spread wide to Gabriel Martinelli, who was granted the freedom of Craven Cottage to surge his merry way down the left flank unimpeded as he reached the Fulham penalty area, cut inside and aimed a shot towards the far post.

Related: ‘A painful day’: Arteta says defeat at Fulham is low point of Arsenal’s season

That Leno was able to palm it away mattered for no more than a split second as the rebound had the misfortune of hitting Saka’s right foot concurrently with the Arsenal winger poking his leg forward – not so much guiding it into the net as prodding in the right direction and hoping the ricochet would end favourably. It did, although the visitors’ joy on a torrid afternoon was short-lived.

With a calf problem ruling Oleksandr Zinchenko out of the match‑day squad, a galling outing for his replacement, Jakub Kiwior – noticeably targeted in Fulham’s first-half attacks – ended prematurely when he was hooked at half-time in favour of Takehiro Tomiyasu.

The Japan defender knew little about his role as the assist provider for Fulham’s second. João Palhinha’s header back across goal from a Fulham corner deflected off an Arsenal head, leg and finally Tomiyasu’s shoulder before falling perfectly for De Cordova-Reid to stab home from close range.

As the most torrential sudden downpour forced any uncovered spectators to scramble for shelter, Arteta tried his best to alter an outcome that looked worryingly inevitable. The introduction of Jesus and Leandro Trossard meant a switch to 3-5-2 and coincided with the visitors inevitably enjoying more time in advanced positions against a progressively deepening Fulham.

But an equaliser never appeared likely and the gloomy mood of the travelling fans could so easily have worsened.

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Raya was first required to pull off a spectacular flying save to deny Cairney’s curled long-range effort which looked destined for the top corner. Then in the dying minutes, the Fulham substitute Andreas Pereira drilled a free- kick against the crossbar.

There have been mitigating circumstances or viable explanations for dropped points in most of Arsenal’s recent games. Not this time. Fulham totally outplayed them, and that is of great concern.