It is faintly ridiculous to suggest that a team that had scored 45 league goals in 16 matches has a problem in attack, but the fact is that Manchester City's defeat away to Chelsea highlighted one thing: they need Sergio Aguero.
With Kevin De Bruyne injured, there has been discussion as to which player is the most important to the Premier League champions.
The current conclusion has been Fernandinho, given the Brazilian's unique role and that there is not a specific understudy should he, at 33, suffer an injury. Maybe it is David Silva, but for all the Spaniard's brilliance and the fact that City are a better, slicker side with him, there are reliable options.
But at centre-forward? Right now, the injured Aguero is clearly irreplaceable, not least because Gabriel Jesus is struggling to such an extent that Pep Guardiola deemed he would start away to Chelsea with Raheem Sterling through the middle, although he later switched that to deploy Riyad Mahrez there.
Sterling did not play badly, although Mahrez and, on the other flank, Leroy Sane did. It is hard to envisage that had one or two of the chances City spurned in a first 44 minutes of utter dominance fallen to Aguero, he would not have scored.
Aguero was missed against Chelsea - not just for his chance conversion rate but because of the overall effect of him being in the team.
Aguero has eight goals in 13 league appearances this season, but crucially, with him in the side City's conversion rate is 15.69 per cent, second only behind Arsenal in the league. Without Aguero, City are at 11.11 per cent - below Brighton, West Ham United and Bournemouth, along with the other five teams in the Big Six.
"The first-half we had chances, and we cannot expect to have a lot of chances against a team like Chelsea," Guardiola said.
The good news for City is that Aguero is expected to be fit for Saturday's home game against Everton. The good news for everyone (bar City fans) is that it does appear there will be a title race.
Liverpool are top and in that fight. Can Chelsea force their way in?
Probably not, but this was an extremely important result for them and, more directly, their manager Maurizio Sarri and his methods.
It may have been a performance far from the 'Sarri-ball' domination of possession the Italian demands, but this was partly born of the fact that City keep the ball, as well as a pragmatic realisation that consequently Chelsea would have to defend deeper and break "the press" as they did with the opening goal.
Neither did Chelsea use a recognised central striker, with Eden Hazard deployed as the "false nine", as he has been in the past and, as Sarri hinted, will be again in "big" games.
There was nothing sophisticated in Sarri's approach; it just turned out to be a game more suited to good defending - as epitomised by Cesar Azpilicueta - and energetic, aggressive midfield play.
It was, in essence, a match for N'Golo Kante rather than Jorginho, with David Luiz also deserving an honourable mention. It was his raking cross-field pass that opened up the pitch for Kante to score with Chelsea's first attempt on goal, and it was Luiz who rose to steer a header, from Hazard's corner, in off the crossbar for the second goal.
For both, there were City errors, not least Sane's failure to track Kante, but why also was sub Ilkay Gundogan marking Luiz at the corner?
City did not play poorly. They were sublime in the first-half, but they did miss Aguero. It is the kind of comment that infuriates managers, not least Guardiola. "Nobody knows," he said when asked whether his team would not have lost with the striker. Of course, he is right. It is hypothetical, but there is a weight of evidence.
The Daily Telegraph
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