Manchester United's poor start to the Premier League season sees them sit eight points behind runaway leaders Arsenal after 10 games.
It may be early days to consider Arsenal title challengers and to rule Manchester United out of contention, but it remains a fact that United have dropped points where champions don't.
A loss to West Brom and a draw against Southampton at home are not the kind of results that usually merit a trophy at the end of the season.
For Robin van Persie, Manchester United's lack of dominance post-Sir Alex Ferguson must be a real concern, not least because he faces the team he abandoned just 15 months ago on Sunday.
It all looked so rosy for the Dutch striker 10 months in to his Old Trafford career. He had his Premier League winners medal and another Golden Boot. Meanwhile Arsenal were still struggling for fourth place.
But the tables have turned. Arsenal have bought every striker's dream in Mesut Ozil and his replacement, Olivier Giroud, is positively flourishing.
Arsenal have rocketed to the top of the table and sit five points clear, eight ahead of Van Persie's United.
A win for the Gunners at Old Trafford would come as no surprise considering they have won 13 out of their last 14 on their travels, drawing the other.
A win would go a long way to stapling Arsenal's title credentials, which are still correctly under intense consideration. This is their first big test of the season but, if they pass it, they'll put 11 points between themselves and the reigning champions.
And that win would not only put a premature end to Manchester United's title defence, it would leave Van Persie embarrassed, looking on as the club he treated so mercilessly flourishes in front of his eyes.
Whether his Premier League winners medal vindicates his decision to leave the Emirates is open to debate, but if Van Persie was told Ferguson would retire one season in to his four-year deal, would he have been so keen to leave the Emirates?
Regardless of your viewpoint, it goes without saying that it would have made Van Persie's decision much harder.
Ferguson inspired an average Manchester United side to a Premier League title purely on his reputation. Without him, they were always bound to struggle and will continue to do so over the coming years - probably for the rest of Van Persie's prime.
David Moyes is not a bad manager, but he has a big mess to clean up at Old Trafford and it will take years for him to get to grips with the enormity of the task at hand.
Now Van Persie gets the chance to look back at what he left last year and will surely fear the sight of much greener grass at the Emirates.
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