Just when Arsenal appeared clear favourites for the Premier League title, the pendulum took another almighty swing last weekend.
Mikel Arteta would be the first to admit that it was never going to be a free run at the prize he has loing been chasing, but supporters are once again concerned.
While the Gunners dominated the attacking statistics against Manchester United, Michael Carrick's men showed more desire and were clinical when it mattered.
The 3-2 defeat last weekend means that the North Londoners lost their unbeaten home record and have now been beaten by United, Liverpool and Aston Villa this season.
With their form against the 'big six' coming into question, could their struggles against their closest rivals cost them the grandest prize?

While the term 'big six' has been misleading in recent seasons, five of those clubs do currently make up the top six in the Premier League table.
The Gunners, Manchester City, Liverpool, Chelsea, United and Tottenham make up that group based on their recent history and financial might, although Spurs are closer to a relegation battle than the European places.
And it is against these sides that Arteta's men have struggled the greatest this season, picking up nine points from a possible 21.
Indeed, Arsenal's only two wins against the collective came against the Red Devils on the opening day - a game they were far from their best - and the North London demolition job over Thomas Frank's men in November.

A glance at the Gunners' results against the big six will tell you that they have struggled to convert chances, having only scored more than once against Tottenham and the Red Devils.
This has also been a familiar problem in recent Premier League matches, with two goalless draws against Nottingham Forest and Liverpool prior to the United defeat.
In fact, the only occasions Arsenal did not record more shots than their big six opponents were against United on the opening day and Enzo Maresca's Chelsea in late November.
During the summer transfer window, the Gunners finally acquired an established number nine in Viktor Gyökeres, but he has become something of a joke in the Premier League.
The big Swede only has five league goals to his name and has struggled to get himself involved in the Gunners' build-up play.
When leading the line for Sporting, the forward benefited from running in behind, but with Arsenal consistently facing low blocks, it has not suited his natural game.
It is no surprise that Arteta favoured Gabriel Jesus against United, but this is an issue that could again thwart the North London club against the big boys.

With the gap at the top of the Premier League now just four points, the remaining matches against the big six will prove pivotal.
While a short away trip to Spurs should yield three points, the visit of Chelsea and the trip to the Etihad are the two that could define who lifts the trophy at the end of the season.
The meeting between Arsenal and City in mid-April will surely be the clash of the season, and it is a fixture that the Gunners have suffered in recent history.
Although the North London outfit have picked up successive draws at the Etihad, they have not tasted victory on away turf since 2015.
Needless to say, the title may be lost elsewhere, and the only thing that Arteta can focus on right now is the trip to Leeds United this Saturday.
If the Gunners are to prove that they are worthy champions, then they must pick up wins against their big rivals or risk relying on them to slip up once again.
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