Erling Haaland said he is confident Pep Guardiola will solve Manchester City’s crisis after they fell to a ninth defeat in 12 matches, an alarming run in which they have won once. The Norway striker conceded he has been out of form but the City manager insisted his team would be worse off without Haaland.

City, who have won only one of their past seven Premier League matches, were beaten 2-1 at Aston Villa to leave them seriously off the pace in the title race, denting their hopes of becoming champions for a fifth successive season. City trail the leaders, Liverpool, who have two games in hand on them, by nine points. “He won the Premier League six times in seven years, so we will never forget that,” Haaland said of his manager. “He will find the solutions. He has been doing that every single year. We still believe in him, we have to work harder than ever right now.”

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A rotten run of results since the end of October has seen City exit the Carabao Cup and drop out of the top four, and has put them at risk of missing out on the Champions League last 16. Phil Foden scored a late consolation after goals from Jhon Durán and the former City midfielder Morgan Rogers consigned Guardiola’s side to an unprecedented sixth league defeat in eight matches.

Afterwards, Guardiola defended Haaland, who did not register a shot and had a single touch in the opposition box. “We have to continue [working to put it right],” Haaland said. “The first [person] I’m looking at is myself, I haven’t been doing things good enough, I haven’t been scoring my chances and everything. I have to do better, it’s a lot on me and I haven’t been good enough.”

Asked about Haaland’s self‑critical reflections, Guardiola, whose side host Everton on Boxing Day, said: “I’m not agreeing with him. Without him we would be even worse. But I like the players feeling that way. It’s the only chance that we have to get better. There are two options: judge yourself or blame. I’m not agreeing with Erling because we tried and at the end he needs to be delivered the right balls in the right spots. We will recover and fight for the next one.”

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Haaland said confidence levels are low in the squad. “Of course, they are not the best. We know how important confidence is and you can see that it affects every human being. That is how it is, we have to continue and stay positive even though it is difficult. We have to keep working hard.”

Rogers, who spent four years at City after joining aged 17 from West Brom, was superb and Guardiola conceded timing prevented the now 22-year-old from breaking into his side. “It was the team that won the treble, the quadruple. Of course, everyone knows how good Morgan is. At that moment, we had players that allowed us to create the most successful eight years in football history.

“Sometimes when they arrive they are three years younger, at that moment there are players in their prime: David Silva, Bernardo [Silva] and Riyad [Mahrez] and Raheem [Sterling]. Sometimes it’s difficult and that’s the only reason why. Of course now these types of players would be with us but it’s always about the right moment. I’m happy for him as he’s a lovely guy, he exploded last season and this season. England have another exceptional, top-class player.”