Anybody who thought retaining the Barclays Premier League was a mere formality for reigning champions Chelsea need think again after Sunderland blew the title race wide open with an emphatic 3-0 victory at Stamford Bridge on Sunday afternoon.
Form students can be forgiven for thinking three points were in the bag for the home side, when you consider that Steve Bruce's side were tasting victory away from home for the first time in the league this season.
Chelsea may point to the fact they had several key players missing including Michael Essien, Frank Lampard and perhaps more importantly captain John Terry, but that would be just making excuses for what was a truly woeful display.
Sunderland themselves had to make do without their top scorer Darren Bent, who is currently nursing a hamstring injury, but it was his replacement and club-record signing Asamoah Gyan who proved the chief architect in Chelsea's downfall.
The powerful Ghanaian star was a constant nuisance to Chelsea's makeshift centre-back pairing of Branislav Ivanovic and Paulo Ferreira, expertly finishing the second of his side's three goals and taking his own personal tally to six goals in all competitions for the Black Cats.
Rather worryingly for Chelsea's fans and backers was the fact that their own forward line never looked at the races on Sunday and after scoring twenty-one goals in their first five league matches, the Blues have now managed only one in their last three.
Every side has their little blips and if that's all you think this is for Chelsea, then the current 1.86 on Betfair for them to retain the title will appeal. But it must be said, they have lost three games already and seem to miss the often-criticised old heads such as Deco, Michael Ballack and Joe Cole, who all left in the summer.
Second favourites at 4.70 are Manchester United, who somehow managed to grab a point from their visit to Villa Park on Saturday, needing to score twice in the last ten minutes to salvage anything from the match.
Clearly nowhere near their best this season, they have however managed to remain unbeaten in the league, although even the most ardent United fan will wonder how. All great sides know how to win ugly and though they are anything but a great side right now, they do possess what their neighbours City clearly lack: a winning mentality.
Two home games against Wigan and Blackburn will lead them into the month of December and six points there would surely see those odds of 4.70 disappear quicker than Audley Harrison's dream of becoming the World Heavyweight Champion.
The 'A-Force' wasn't the only man in Manchester who should be embarrassed by his own Saturday performance. Manchester City manager Roberto Mancini seems incapable of getting the best out of his richly talented squad and appears to be blowing any realistic chance the Sky Blues had of lifting their first ever Premier League title.
Now I'm not one of those who screams for the manager's head every time a couple of results go the wrong way, but it must be said that City are massively underachieving and sole responsibility must lie with the likeable, but ultimately unsuccessful, Italian.
Carlos Tevez gives his all week in and week out but the frustration is clear for all to see as the little Argentinian fights to feed from the scraps created by a defence-minded midfield. Nigel De Jong, Gareth Barry and Yaya Toure are predominantly stoppers, ball-winners, scrappers, call it what you will, but not one of them was what you'd call a creative force.
Each time I've seen City of late the same pattern repeats itself. The midfield win the ball, they feed wide-man James Milner, who then whips in a high ball for somebody no bigger than Jimmy Krankie to win in the air against four defenders.
You may disagree but believe me, this squad is good enough under the right guidance to win the Barclays Premier League. Unfortunately for City supporters I'm afraid that's not Roberto Mancini and only his departure could make the 21.00 currently on offer with Betfair look attractive.
This weekend belonged to the two North London teams with Tottenham moving to within three points of fourth place after crushing Blackburn Rovers 4-2 and Arsenal, who are now as short as 5.5 with Betfair, rounding off the week in style by showing great spirit to defeat Everton 2-1 at Goodison Park.
So it's all set up for a humdinger of a match this Saturday lunchtime where these two great rivals meet at the Emirates Stadium. A win for Arsene Wenger's men will see them go top and unless Chelsea can recapture some of the sparkle showed earlier in the season, then who knows how long they could stay there....
By Dean Goddard
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