There doesn't appear to be much wrong with Manchester City, but manager Pep Guardiola is wearing the expression of a man who fears that the roof is about to cave in at any moment. Last season's Premier League champions have started this campaign with 17 goals in six games across all competitions and they sit three points behind title rivals Chelsea, Liverpool and Manchester United with the race barely into its first lap.

A 6-3 win against RB Leipzig in the Champions League last week put City in control of Group A following Paris Saint-Germain's surprise 1-1 draw against Club Brugge. If City can win at Parc des Princes next week, five months after a 2-1 victory in Paris in last season's semifinal first leg, they will have one foot in the knockout stages before the autumn leaves have started to fall.

But Guardiola is not at ease with his team's situation right now, and perhaps that is because of the trio of crucial games that they must negotiate over the next 13 days. The consequences of City's failure to sign Harry Kane or Cristiano Ronaldo to replace Sergio Aguero as the focal point of their attack might be about to hit home.

After what should be the formality of a Carabao Cup third-round tie at home to League One side Wycombe on Tuesday (Stream LIVE on ESPN+ from 2.30 p.m. ET), City embark on three away games that could shape their season.

Saturday's Premier League trip to Chelsea is followed by that clash against PSG three days later. And then comes a visit to Liverpool on Oct. 3 for a renewal of the rivalry with Jurgen Klopp's in-form team at Anfield.

City are more than capable of winning all three of those games and banishing the negativity that has begun to creep in since Guardiola lit a fuse by highlighting the need for more supporters to get behind his team after 38,062 turned up for the Leipzig fixture. Saturday's 0-0 draw at home to Southampton was watched by 52,698 fans, but the final result, after City had managed only one attempt on target, merely added to Guardiola's frustration.

"Always when the game is not good I feel bad," Guardiola said after the game. "[The fans] come to see a show, to see a game. When it doesn't happen, I feel a bit guilty because we didn't play good."

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Publicly, Guardiola has insisted that missing out on Kane and Ronaldo has not affected his team's ability to score goals and win games, but most football managers are smart when it comes to picking their battles, and the former Barcelona and Bayern Munich coach is not naive enough to criticise City's owners for failing to deliver the centre-forward his team clearly needs.

Jose Mourinho is a rarity in that respect. He has regularly complained about unsatisfactory recruitment at previous clubs and the end result has usually always ended with him leaving the club fairly soon afterward. Others, such as Klopp or Sir Alex Ferguson during his time at United, focus their anger or annoyance on referees or opponents, knowing that targeting owners or players is often a recipe for bigger problems.

By criticising City's fan base, Guardiola used a proxy to air his frustrations and maybe even his fears over what lies ahead. His team face an acid test of their credentials over the course of the next two weeks, and they are not ready.

City climbed from mid-table last season to win the title, ultimately topping the table with a 12-point margin, but the field is much stronger this time around, and Guardiola knows that his team cannot allow Chelsea, Liverpool and United to pull clear. A defeat at Stamford Bridge at the weekend would leave City six points behind Thomas Tuchel's team and intensify the pressure ahead of the trip to Anfield, but Guardiola has no obvious solution to his centre-forward problem.

Raheem Sterling, who started as a false No. 9 against Southampton, has scored just two goals in his past 22 appearances in all competitions, while Kevin De Bruyne has yet to score this season as he makes a tentative return to action from a troublesome ankle injury. Gabriel Jesus, the only recognised striker in the squad, has scored just twice in six appearances this season -- the same return as Ferran Torres, though Torres has been favoured in the No. 9 role more.

Ronaldo, meanwhile, has shown the true value of a goal scorer by netting three in two league games for United since rejecting City to return to Old Trafford from Juventus last month. And at Chelsea, Romelu Lukaku's three goals in four games are a big reason why the club sit on top of the Premier League right now. As for Liverpool, Mohamed Salah continues to show why he is arguably the most reliable and consistent scorer in the league with four in five games so far.

City don't have a Ronaldo, Lukaku or Salah. They have plenty of threat in attacking positions, of course, but all top teams need a player who will score at least 20 league goals in a season, and Guardiola knows he doesn't have one of those. However, rather than complain about it in public, he has chosen instead to let off steam by singling out the club's supporters.

Time will tell whether Guardiola's mood will change, but you can bet that the outcome of City's next three away games will play a big part in shaping his demeanour.