Manchester City were booed by their own fans and manager Pep Guardiola was even jeered by Manchester United fans who chanted "you'll be sacked tomorrow morning". At the Etihad, Amad Diallo's late goal sealed a 2-1 win for the visitors.
Man City have now lost eight of their last 11 games in all competitions - their worst run since 2003. The Citizens' hopes of defending the Premier League title are now in tatters. According to ESPN Research, Man City have lost more games this season than in their previous 106 games combined.
Josko Gvardiol's first-half header looked set to seal victory for City as United missed a series of chances to equalise in the second half. However, Matheus Nunes' foul on Amad in the 86th minute led to a penalty that Bruno Fernandes converted. Just two minutes later, it was Amad who silenced the Etihad with the decisive goal.
The current crisis has gone beyond Guardiola's control. Just a few days ago, The Citizens also suffered a 0-2 defeat against Inter Milan in the Champions League.
Man City went into the match against Man United determined to win and get their season back on track. However, they played poorly even when they had the advantage. The image of a team that had won the Premier League four times in a row was gone. As a result, Man City allowed Man United to rally late in the match and stage a remarkable comeback.
City's problems are clear. They lack pace in key areas and key players have fallen off the pace. Kyle Walker, Kevin De Bruyne, Ilkay Gundogan and Bernardo Silva simply cannot cope with the intensity of games at the highest level.
The biggest headache for Guardiola is probably the loss of form of key striker Erling Haaland. The Norwegian player was completely obscure and was neutralized by Harry Maguire.
Haaland has now scored just six league goals since the end of August and has only three in his last 11 games. When he doesn’t score, Haaland doesn’t contribute much to the team’s overall play. It’s clear that opponents have found a way to either weaken Guardiola’s defence or nullify Haaland.
This is the biggest challenge of Haaland's career. The Norwegian striker must prove he can do more than just score goals when his team is flying high.
Guardiola, meanwhile, has said he is not going anywhere, having signed a new two-year contract last month. But how long can that last when even Guardiola's position is under threat?
"I'm a coach and I'm not good enough. I didn't do well. That's the truth. That's how it is. What can I say? We can't blame this player or that player, that's not it.
"It's been a difficult season for Man City. We haven't been at our best. Something's not right, losing eight out of 11 games is unusual," said the Spanish tactician.
