Raheem Sterling’s third-minute opener was cancelled out by Jamie Vardy, as both teams went into half-time level-pegging.
Then came the fireworks.
Aguero netted his first on 48 minutes before putting another three past Kasper Schmeichel, with his fourth and final goal coming on the 90-minute mark.
Leicester, meanwhile, remain in eighth spot despite enduring a torrid evening at the hands of Aguero and co.
Here are three talking points…
Aguero issues a timely reminder to Pep Guardiola
There is only one place to start.
At times, this has been a difficult season for the Argentinian sharpshooter, who has often played second fiddle to Gabriel Jesus in the crunch fixtures and cut a frustrated figure on the sidelines.
However, the Brazilian’s injury opened the door for Aguero and he has barged through, reminding Pep Guardiola why he can still play a major role as City fight on three fronts; in the Premier League, FA Cup and Champions League.
Aguero was at his predatory best against a Leicester side that were far too accommodating in the second period and, with Kevin de Bruyne pulling the strings in behind, the Argentine has the perfect foil.
All the talk right now is about Harry Kane, but Aguero is only two goals behind the Tottenham man in the goalscoring charts, after netting in his seventh straight game at the Etihad.
This tally has also seen the 29-year-old surpass 20 goals for the fourth successive season.
Off-field issues undermine Leicester
With such a major distraction off the pitch this week, a visit to the runaway leaders was not the ideal fixture for Leicester manager Claude Puel.
Riyad Mahrez had dominated the headlines in light of his failure to report for training.
A U-turn saw him make himself available for the City clash, but at such short notice he was only afforded a place in the substitutes bench, coming on just after the hour mark.
Mahrez has acted unprofessionally after a deadline-day move to City was blocked by the club and he will have bridges to build with the club’s supporters.
When Vardy scored for the fourth game in succession to equalise, those fans would have hoped that they could return to the Midlands with a point.
Alas, City flexed their muscles after the interval and extinguished such aspirations.
But Leicester, in the comfort of eighth spot, can hopefully look forward with their best player back in the right frame of mind.
De Bruyne sparkles like a real diamond
This week, Chelsea playmaker Eden Hazard was honoured with Belgium’s player of the year award.
Perhaps that was the spur for de Bruyne to produce another virtuoso performance.
He was always at the heart of City’s attacking play, the conductor of the orchestra who is at the peak of his powers.
De Bruyne assisted City’s first three goals to take his tally for the season to 14 – four more than his nearest challenger.
The cross that teed up Sterling was perfectly weighted, so was the delivery that enabled Aguero to open his account.
Another sumptuous ball from de Bruyne for the Argentinian left him with the opportunity to double his tally, which he duly took.
Football is subjective, but it is hard to believe at present there is a better midfielder in Europe than de Bruyne – that includes Hazard.
Belgium are fortunate to have them both in their ranks.
Wrapping them up in cotton wool will be crucial to their World Cup bid.
One winner and loser from Leicester’s defeat to Manchester United
A new season for Leicester began with a 2-1 loss at Old Trafford.
An early penalty from Paul Pogba added to Luke Shaw’s first senior goal condemned Claude Puel’s side to defeat on the opening night of the new season, which brought a case of deja vu to supporters after the 4-3 defeat to Arsenal on a Friday night 12 months ago.
Leicester enjoyed plenty of possession in their trip to Manchester, putting Jose Mourinho’s side under a lot of pressure, but failed to make it count as David De Gea was largely untested. While some impressed, there was others who need to improve.
Here, we have identified one winner and one loser from the game.
Winner: James Maddison
Signed from Norwich City, James Maddison arrived at Leicester City with plenty of expectation as he was widely regarded to be one of the best players outside of the top-flight last season. From the early signs, there is a lot to be excited about.
Maddison proved to be the creative hub for Leicester throughout the match, central to anything positive that the Foxes created and not afraid to get stuck in – with a stern battle up against Manchester United’s new recruit Fred in the heart of midfield.
Having scored 14 goals and contributing eight assists last season, Maddison should be able to provide the spark in the final third that Claude Puel’s side lost following the sale of Riyad Mahrez to Manchester City.
Loser: Daniel Amartey
If you were to describe the worst possible start to a new Premier League season, conceding a penalty just minutes into the opening game would certainly be right up there – and Daniel Amartey was the unfortunate party last night.
His handball mere minutes into the new campaign saw Paul Pogba score from the spot and the Ghana midfielder struggled to get a foothold in the match from then on, riding his luck with a few clumsy challenges before picking up a deserved yellow card.
He was taken off by Puel in a double change shortly after the hour mark and may now face a test to retain his spot in the side.
Three things learnt from Leicester’s defeat to Manchester United
For the second year in a row, Leicester began the season with a Friday night defeat.
Paul Pogba’s penalty mere minutes into the match left Claude Puel’s side trailing early on and, despite plenty of possession, the Foxes failed to make it count and Luke Shaw’s first senior goal ensured all three points were secured by the home side, despite Jamie Vardy’s late consolation.
Going to Manchester and taking a result off a Jose Mourinho side is never an easy task but fans will have wanted to see more from their side given the possession that they had, which has left plenty of room for improvement over the coming weeks.
Here, we have identified three things we learnt from the result.
In an away game against a side like Manchester United, set-pieces are always going to be valuable as clear-cut chances are often few and far between. On top of that, Harry Maguire enters the campaign on the back of an excellent World Cup with England where he was highly effective from a dead ball situation.
However, Leicester failed to create anything of note from the free-kicks and corners they earned – which will be a major area for Claude Puel’s side to improve over the coming weeks if they are to enjoy a more successful campaign this term.
Clearly the loss of Riyad Mahrez, who was the regular set-piece taker, to Manchester City has seen the Foxes take a hit and they will need the players within their squad to step-up in order to provide opportunities from this positions.
Still just 21 years of age, it seems like Ben Chilwell has been up and coming for a while but he already boasts over 30 league appearances for the Foxes. He will now be focused on becoming a regular part of Claude Puel’s side and the early signs are positive.
Chilwell proved to be extremely effective as an attacking outlet down the left-side for the Foxes, causing Manchester United problems, but the lack of support ahead of him proved to be an issue. However, with Jamie Vardy returning to action and James Maddison now part of the squad, there’s a real chance for a strong relationship to develop.
With Christian Fuchs now 32, Chilwell could become first-choice this season and could even start to push for a spot in the England squad.
“Chilwell is a young player without experience but with good attributes to take the space to join in attack also. It is a good choice for me with good opportunities.”
Lack of cutting edge
Unfortunately for Leicester, the absence of Jamie Vardy at the front of the attack, fresh from signing a new four-year deal, was obvious as the Foxes struggled to test David De Gea – and he proved his worth by scoring a late goal off the bench.
Had Vardy started from the off, Manchester United’s defence would have had a much harder game on their hands as his pace and drive would have put the Red Devils defence, which Jose Mourinho famously doesn’t rate all that highly, under real pressure.
Kelechi Iheanacho was the man who led the line at Old Trafford but he did not really get a sniff at goal, while the wingers often struggled to find space to work with when they broke into the final third and the majority of their play came in the middle area of the pitch.
One to watch: West Brom’s 20-year-old midfielder Harvey Barnes
Introducing The Boot Room’s 2018/19 One to Watch series…
There are high hopes for Harvey Barnes at Leicester City.
Earlier this summer, Barnes signed a new four-year deal before being loaned out to West Bromwich Albion for the upcoming Championship season.
He already has second-tier experience, after scoring five goals and assisting four in 1,408 league minutes on loan for the first half of last season with Barnsley.
Barnes has already smashed in an absolute pearler this season, highlighting the danger he presents from range.
The direct threat he poses from out wide – he likes to start wide and drift inside where he is capable of shooting accurately on either foot – is an increasingly desirable trait in modern football.
Conversely, he is also adept at playing the final ball in such situations.
Sometimes, he simply just likes to take up position in the channel from the start.
Darren Moore praised Barnes upon his arrival, pointing towards the Englishman’s X-factor.
“He is an exciting young player – one that I think our supporters will enjoy watching,” Moore told the club website.
“He’s got good experience of the Championship already and I am thrilled at the prospect of him adding his talents to our group. I couldn’t be happier that we have been able to bring him in.”
Those comments are promising to hear as Barnes looks to get minutes under his belt in view of returning to his parent club and being integrated there.
In the meantime, it will be fascinating to see if he can put together a consistent 42-game Championship season.
He did well for six months last season before he was recalled in January by Leicester.
West Brom will certainly be leaning on him as a key pillar in their hopes to return straight back into the Premier League.
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