Manchester City have lost three consecutive games in a season for the first time since April 2018 following Tuesday's 4-1 Champions League reverse against Sporting.
The defeat is City's worst since a 5-2 thrashing by Leicester four years ago. It is only the third time a Pep Guardiola team has shipped four goals in a Champions League game.
Bernardo Silva said afterwards that City are in a "dark place" - but what are the issues they face? Are fans right to be worried? And what do the stats say about their performances?
- Man City in a 'dark place' - but Pep Guardiola is ready for the challenge
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Injury struggles continue
Guardiola warned ahead of the defeat at Sporting that Man City would struggle to overcome their mounting injury list.
"We know we will struggle and we have to accept that, and it is fine," he said. "The games will be difficult; in previous seasons it was smooth. Personal reasons, injuries, we won six Premier Leagues in seven years. Things change, we have to accept that."
Guardiola handed a first senior start to defender Jahmai Simpson-Pusey in Lisbon to underline the issues he has, particularly at centre-back, where Ruben Dias and John Stones are out injured.
Jack Grealish is also still out and add in the long-term injuries to Ballon d'Or winner Rodri and Oscar Bobb, and Man City's resources are heavily depleted.
Manuel Akanji was fit enough to start against Sporting but has had injury niggles of his own, while Nathan Ake was an unused substitute. Rico Lewis deputised again for Kyle Walker, who was only fit enough to be named on the bench.
A positive was the sight of Kevin De Bruyne back on the pitch but the Belgium international was only called upon for the final six minutes of the heavy defeat, while Jeremy Doku also got minutes from the bench.
It's not totally clear who Guardiola will have back for Saturday's trip to Brighton, live on Sky Sports, but Guardiola is searching for solutions as City look to avoid a fourth straight defeat.
"It happened in my first year," he said. "Sometimes it does. I have to try to find an explanation but sometimes it's just football, so you have to accept it. Sport is that. Life is that.
"Sometimes we have bad moments but we face the reality. Everyone has to try to be better and we will find it. We are still alive in all competitions and we continue."
Haaland needs help
The Norway forward cut a frustrated figure after seeing his second-half penalty crash against the crossbar in Lisbon.
He has now gone two games without a goal and by the lofty standards he has set since arriving in England, that is a drought.
The worry for City is not regarding Haaland and his form - as the goals will inevitably return for him - but the support he has around him.
Five games back in 2023 is his longest run without a goal for the club but City still went undefeated throughout these fixtures, winning four and drawing one, as they leaned on the talents of Julian Alvarez, Phil Foden and many others in the squad.
The departure of Alvarez, a drop in form for Foden and injuries to other key players like Rodri and De Bruyne have now caused goals to dry up for those around Haaland.
City's squad currently offers little support in this area, which is highlighted by defender Josko Gvardiol currently being tied for second for goals across all competitions, with three.
So if Haaland struggles, the team now suffers more than ever.
Sporting highlight fast-break frailty
There was a familiar feel to Sporting's first two goals on Tuesday night, with Gyokeres and Maximiliano Araujo the latest players to get in behind Man City's defence and profit from their growing vulnerability from quick and direct attacks.
Those goals were not the only examples in the game, with Gyokeres missing an earlier one-on-one having been put through on goal from inside his own half following a transition. The penalty for Sporting's third came after Francisco Trincao had got in behind in similar fashion.
Bournemouth and Tottenham were able to cause problems for City in the same way, but it has been happening throughout the season. Amazingly, City have allowed 10 more shots from fast breaks than any other Premier League side in all competitions.
They are giving up chances from fast breaks at a rate roughly three-times higher than last season. Rodri's absence is a factor but it is worth noting that, before his injury, the Spaniard started one of the games in which the issue was most apparent, the goalless draw with Inter Milan in September in which City gave up four shots from fast breaks.
The loss of the injured Kyle Walker's recovery pace is probably a bigger contributor. But his struggles against Fulham's Adama Traore, in a game City were lucky to win, added to the feeling that, at 34, he might not be the solution he once was behind their back line.
The root causes can be debated but City's frailty from fast breaks is an issue their opponents are exploiting with increasing regularity.
But is Pep right on performance levels?
Guardiola disagreed with Bernardo Sila's assertion that City are "in a dark place" after the Sporting game, insisting their display was "really good", despite the emphatic result.
It was not the first time he has defended their performance levels recently and the underlying numbers suggest he has a point. City have failed to win two of their first four Champions League games but Sky Sports' 'expected points' table has them two points better off.
That is not much comfort to City fans in the aftermath of such a heavy defeat but they remain on track for automatic qualification to the knockout stages, and the numbers support the argument that their performances have been better than their results suggest.
The same underlying metrics show no great drop-off domestically either. City won the Premier League title last season with the second-highest expected goal difference in the division and sit in the same place now, albeit just behind Liverpool rather than Arsenal.
Expected goal difference is regarded as a key performance indicator by clubs and offers hope to City that their fortunes could change.
Are alarm bells ringing at the Etihad?
"I won't give up, that's for sure," Guardiola said after the loss to Sporting.
This is new territory for him and his City side, who have grown accustomed to dominating English football since his arrival in 2016.
The off-field issues surrounding the club are well documented with the exit of sporting director Txiki Begiristain and the alleged breaches of financial rules looming over them.
But up until now, his team had not faltered.
Is the pressure of the outside noise finally seeping into the dressing room? His public disagreement with Silva's post-match comments about the team being in a "dark place" could suggest so.
"I don't agree with him. We are not in the dark side," he continued.
"We played really bad against Bournemouth but really good here. The only regret is conceding the third and fourth - the penalties were not necessary.
"We knew it would be a tough season at the start and this is what it is. I like it, I love it, I want to face it and lift my players. Life is like this. We continue.
"What should we do? We go back to Manchester and prepare for the game at Brighton."
Further tests to come
Things don't get any easier for City as they face a fourth away game in 10 days when they travel to the south coast to face Fabian Hurzeler's Brighton on Saturday, live on Sky Sports.
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However, one positive is that this is City's final game before another international break, which could be a crucial two-week period for Guardiola to get some of his injured stars back.
Grealish, Stones and Dias are all rumoured to be returning after the break, when City host Tottenham at the Etihad Stadium on November 23, live on Sky Sports.
Throw in a Champions League game against Feyenoord before a mouthwatering clash with league leaders Liverpool at Anfield on Sunday December 1, against live on Sky Sports, and a midweek fixture against high-flying Nottingham Forest on December 4.
There's also a trip to Selhurst Park before Guardiola again comes up against Ruben Amorim in the Manchester derby on December 15, live on Sky Sports.
This is no easy run. Man City's squad will be severely tested in the coming weeks and it could be make or break for their season.
(c) Sky Sports 2024: Man City's heavy loss to Sporting CP takes them to 'dark place' and shows problems facing Pep Guardiola