"What we have learned is not only that Manchester United could beat Arsenal, but that everybody can beat everybody in this Premier League. Maybe the whole quality of the league has gone up."
That was the verdict of Arsene Wenger in the wake of the Gunners' 1-0 defeat at Old Trafford on Sunday, and while the north London side remain out in front in the Premier League, their advantage has been cut to two points with eight teams now within six points of the summit.
Several shock results this season would give weight to Wenger's argument.
Manchester City losing to Sunderland on Sunday was the latest in a succession of unexpected outcomes which has seen United beaten at home by West Brom, the Gunners humbled by Aston Villa at the Emirates, Chelsea slip up at Newcastle, Liverpool fall at home to Southampton, and struggling Norwich inflict the third-placed Saints' solitary defeat.
But there is an equally valid counter-claim. Rather than the chasing pack catching up, there is evidence that the established elite have faltered. Managerial changes for all of last season's top three were bound to have an impact - particularly at Old Trafford following the retirement of Sir Alex Ferguson - and the extent to which United, Chelsea and City have allowed points to slip away cuts through the cloak of invincibility they may have enjoyed in the past.
Since the inception of the Premier League in 1992, there has only been one season in which the top eight have been more compact at this stage - back in 2001-02, when leaders Aston Villa were just four ahead of Tottenham, with Arsenal going on to be crowned champions that term by seven points from Liverpool in second.
With 27 games of the campaign still to come, we assess the top eight and evaluate how they will fare in what promises to be the most competitive Premier League title race in over a decade.
Points 25 Sky Bet odds 7/2
For - Rather than playing catch-up as has been the case so often previously - having been 11, 12 and five points behind the leaders at this stage in the last three seasons - Arsenal are leading from the front. Aaron Ramsey's stunning form means he is overshadowing marquee summer signing Mesut Ozil in a midfield coping well with injuries to key men.
Against - The lack of alternatives to Olivier Giroud must be a concern for Wenger. The France international has already made 21 appearances for club and country this season with Lukas Podolski in the treatment room and Nicklas Bendtner miserably out of form. The January transfer window is approaching, but Wenger may be reluctant to invest mid-season.
Points 23 Sky Bet odds 13/2
For - The lethal partnership between Luis Suarez and Daniel Sturridge sees the duo alongside Sergio Aguero at the top of the Premier League scoring charts having each found the net eight times, with the form of the Uruguay international even more remarkable given he was suspended for the opening six games of the season.
Against - As with Arsenal, there is a concern over lack of depth behind the first-choice forwards, while Brendan Rodgers appears unsure over his favoured defensive line-up after tinkering with formations and personnel. All is well in the Suarez camp at present, but the summer saga over his future remains fresh in the memory.
Points 22 Sky Bet odds 125/1
For - A defence which is the envy of the Premier League with only five goals conceded in 11 games is coupled with a team which has embraced Mauricio Pochettino's high-energy pressing game with gusto. With three attacking players in the latest England squad, there are plenty of reasons to be cheerful in the stands at St Mary's.
Against - Even the most ardent Saints fan would admit that the depth of their squad does not measure up to big guns of the Premier League. The immediate fixtures after the international break will be a test, too, with a trip to Emirates Stadium immediately followed by a clash at Stamford Bridge, while Manchester City and Tottenham will arrive on the South Coast in December.
Points 21 Sky Bet odds 7/2
For - Jose Mourinho's return to Stamford Bridge has seen him take over a squad packed with creativity and quality in the playmaking department coupled with strength and resilience in defence, and sufficient depth in most positions. Mourinho, too, boasts a staggering record which has seen him collect at least one trophy in eight of the last nine seasons.
Against - Question marks remain over Chelsea's forward line, despite Fernando Torres showing flashes of his pre-£50million self in recent weeks and Samuel Eto'o is another whose reputation currently outweighs his contribution. Mourinho's willingness to loan out Romelu Lukaku remains baffling, given his top-flight contributions to West Brom and Everton.
Points 20 Sky Bet odds 9/2
For - Robin van Persie and Wayne Rooney demonstrated perfectly against Arsenal why the reigning champions cannot be written off, with the energy, drive and determination of the latter complemented by the former's finishing prowess. This squad finished last season 11 points clear of the chasing pack, the biggest winning margin since 2004/05 when Chelsea were 12 ahead.
Against - Life after Ferguson was always going to be tough, with Moyes on an incredibly steep learning curve with his every selection and interview scrutinised to the nth degree. A disappointing summer transfer window still rankles with solitary signing Marouane Fellaini not the creative midfield addition fans had hoped for.
Points 20 Sky Bet odds 125/1
For - The deadline day signings of Romelu Lukaku and Gareth Barry brought attacking vigour and midfield nous to Roberto Martinez's squad, while retaining the services of Leighton Baines was equally important to their defence. Everton swiftly embraced the passing and possession game favoured by the former Wigan boss and have suffered just one defeat - at Man City - so far.
Against - As with Southampton, Everton have some testing fixtures looming on the horizon, with the Merseyside derby at home to Liverpool immediately after the international break swiftly following by trips to Manchester United and Arsenal. Arouna Kone's absence through injury and Nikica Jelavic's lack of form leaves Martinez short on striking support for Lukaku.
Points 20 Sky Bet odds 28/1
For - A summer of investment to offset the loss of Gareth Bale has removed the 'one-man-team' tag levelled at Spurs last season and they are three points better off than at this stage last term. The second-best defence - and one of the best goalkeepers - in the league deserve huge credit, while their creativity cannot be questioned as Spurs lead the league in shots on target this season.
Against - An inability to convert those chances is threatening to cost Tottenham dearly, with their shot conversion rate an embarrassing league-worst of 5.73 per cent. Andre Villas-Boas continues to persist with Roberto Soldado, despite the £26million man having scored just once from open play in 11 games in the Premier League.
Points 19 Sky Bet odds 5/2
For - Manuel Pellegrini's men are untouchable on home turf, with 20 goals scored and only two conceded. In-form striker Sergio Aguero has been simply unplayable at times in a City squad brimming with attacking talent, while the club's progress in the UEFA Champions League has removed the pressure from their two remaining European matches this year.
Against - City's record away from the Etihad is utterly woeful, with Fulham having taken more points on their travels. Defeats to Sunderland, Cardiff and Aston Villa is not the form of champions, with City's huge reliance on captain and defensive lynchpin Vincent Kompany evident in the manner with which they have conceded a number of route-one goals this term.