Arsenal & Liverpool excel, Rooney outcast and Moyes' nightmare goes on

Arsenal's win was their heaviest over Chelsea since April 1997 (also 3-0)

Manchester City's flawless start to the Premier League season continued with a sixth successive victory at Swansea City - but the pursuing pack also made an impressive case for their title credentials.

Tottenham remain unbeaten in second place after winning at Middlesbrough while Arsenal and Liverpool dismantled Chelsea and Hull City. Manchester United, without dropped Wayne Rooney, thrashed champions Leicester City after two successive league defeats.

So what were the big issues to emerge from a pulsating day of Premier League football?

What now for Rooney?

Man Utd scored four first half goals for the first time in the Premier League since Dec 2012 (4-3 v Reading at half-time)

Jose Mourinho insisted his 30-year-old captain - left out after early season struggles - was "my man" and Rooney himself joined the celebrations from his place on the bench as the home side flourished without him in an emphatic 4-1 win at Old Trafford.

The United manager said: "I trust him completely. He's as happy as I am at this moment that the team won. He's a big player for me, for United, a big player for this country."

It may not quite be the day that marks the beginning of the end for Rooney's United career but, as well as words of support, Mourinho made a tactical point that suggested he may be spending a lot more time applauding from the technical area rather than the pitch.

Mourinho said: "When our main striker is Zlatan we need fast people surrounding him to bring that intensity to the game."

For all the qualities Rooney still possesses, and there are many, being fast is not one of them and it is clear at this point in time that Ibrahimovic is Mourinho's main striker.

Ander Herrera provided the base for Paul Pogba and Juan Mata to excel and score, while Marcus Rashford and Jesse Lingard provided the pace Mourinho craved.

Mourinho is wise enough - certainly more of an Einstein (as he sarcastically called his critics) than most of us when it comes to football - not to make Rooney feel too marginalised but add Antony Martial and Henrikh Mkhitaryan to the Old Trafford equation and he has a real fight on his hands to earn a place.

Only a fool would write Rooney off and this consummate team man will wait for his next chance but it is now evident that Mourinho has the resources and tactical flexibility to do without his influence on even more occasions in the future.

Can Spurs or Liverpool win the title?

Liverpool's goal tally after eight competitive games this season is their highest in 121 years, since 1895-96

Liverpool's blistering early season form comes with a two-word caveat that they are slowly but surely making irrelevant - namely the phrase "Burnley apart…"

It was that 2-0 loss at Turf Moor in the second game of the season that sends up the only cloud of doubt about a Liverpool team that looks intense, aggressive, attractive and a real threat under manager Jurgen Klopp.

Liverpool have gained seven points from three tough away games against Arsenal, Spurs and Chelsea while Saturday's 5-1 win over Hull City made it nine goals at Anfield following the 4-1 victory against Leicester City.

Klopp can focus on the Premier League without the distractions of European football and so far the results have been impressive, with £34m summer signing from Southampton Sadio Mane giving an extra cutting edge and Adam Lallana in arguably the best form of his career.

The charismatic German is carrying his players and Liverpool's fans with him as they start to believe they can really make an impact this season. Klopp called their beating of Hull City "world class".

Title talk is wildly premature and an occasionally suspect defence will face greater tests as Liverpool go deeper into the season - but Klopp looks like he could easily keep an emerging side in the top four.

Tottenham have taken a "softly-softly" approach into second place. They are now one of only two unbeaten teams in the Premier League, along with leaders Manchester City, after their 2-1 win at Middlesbrough and Everton's loss at Bournemouth.

Mauricio Pochettino's side have been steady rather than spectacular but have ground out wins at home to Crystal Palace and Sunderland while winning impressively on the road against Stoke City and at The Riverside.

The biggest measure of their title aspirations will come when they face Manchester City at White Hart Lane next weekend - and also how they cope with injured striker Harry Kane.

Spurs went close to the title last season so there is no reason to suspect they will not be in the shake-up this term, especially as they are currently second without hitting top form.

And now they have a new inspiration in the revitalised Son Heung-min, the South Korean finally showing his true capabilities after a transitional season following his £20m move from Bayer Leverkusen in August 2015 with both goals at Middlesbrough.

Liverpool's dominance is illustrated clearly by the respective heat maps of the two sides. The Reds are on the left

Will the real Arsenal please stand up - and how bad are Chelsea?

Theo Walcott has scored in consecutive Premier League games for the first time since May 2013

Arsenal's 3-0 win against Chelsea was their first over their London rivals since 2011 and their biggest victory against them since April 1997 - a scoreline reflected in the performance of both teams.

Manager Arsene Wenger has suffered enough at Chelsea's hands, particularly under Mourinho, to be allowed to celebrate this convincing triumph, which he called: "One of the best performances in recent years. We played with style, with pace, with movement - and that is the sort of football we want to play."

The Gunners were simply irresistible, with Alexis Sanchez and Mesut Ozil leading the charge with world-class displays, both on the target and tormenting Chelsea for 90 minutes.

Arsenal were magnificent. The question now is will they be magnificent at Burnley next week, then at home to Swansea City after the international break?

On this form they can beat anyone. In previous seasons they have also proved they can lose to anyone - hence no Premier League since "The Invincibles" season of 2003/04 when they won the title going unbeaten over 38 games.

Wenger has many admirers as he reaches 20 years at Arsenal who would delight in seeing him achieve title-winning status again. Can he unlock the key to consistency that would at least put Arsenal among the main contenders?

For now, though, this enduring purist can revel in a performance from his Arsenal side that was a thing of football beauty.

As for Chelsea, this was an abominable effort, even worse than in defeat by Liverpool at Stamford Bridge.

Manager Antonio Conte must rebuild a team that looks old, jaded and in desperate need of renewal. Branislav Ivanovic and Nemanja Matic look like players in the closing stages of their Chelsea career while England defender Gary Cahill is increasingly vulnerable and accident prone.

David Luiz, predictably, has brought a sense of chaos to Chelsea's defending following the decision to re-sign him in a £32m deal from Paris St. Germain while Cesc Fabregas and Eden Hazard were so poor they could have no complaints at being substituted.

Conte will need time to sort Chelsea out. He will hope demanding owner Roman Abramovich understands the scale of the problems.

Chelsea's defeat was their first against Arsenal in the Premier League since losing 5-3 at home in October 2011

Will Moyes' nightmare end?

Sunderland have not won in their last 25 Premier League games played in the months of August or September

When Jermain Defoe put Sunderland 2-0 up on the hour against Crystal Palace, manager David Moyes must have thought the almost unrelenting footballing misery he has endured on Wearside since succeeding Sam Allardyce was over.

It was not to be - Sunderland could not even hold out for a draw, losing to Christian Benteke's injury-time header to anchor the Premier League with one point from six games.

Sunderland now face a vital home game to West Bromwich Albion next weekend before a visit to fellow strugglers Stoke City - and even at this stage of a season in its infancy, The Black Cats simply have to start getting points on the board.

Moyes hardly lightened the mood around The Stadium Of Light by announcing after two games their season would be a relegation fight but his players are doing nothing to suggest he was being unduly pessimistic.

The Scot needs results himself to restore his confidence and managerial reputation after two sackings at Manchester United and Real Sociedad - and he wants his players to now start doing their bit.

He said: "We're in a similar situation to where the club's been for the last two or three seasons. To address this, when we go 2-0 up, we don't lose headers and challenges.

"The players have got to do their bit and I'm not sure in certain situations they did. Many managers have said similar things and maybe the fans are now used to it. I do think the players need to be big enough to play and do the right things."

It is a parlous position for Sunderland and Moyes once more - and defeats like this, a real kick in the teeth after that first win looked in sight, will only increase the sense of crisis closing in on the club.