After nine successive away victories under the Norwegian in all competitions, they have now gone nine without a win and are already 10 points behind leaders Liverpool.
And it has all come at a time when their two main rivals, Manchester City and Liverpool, are setting new standards at the top of the Premier League.
Jose Mourinho, sacked in December, told Sky Sports after Sunday’s defeat at the London Stadium that he did not see any improvement in United this season, despite the signings of defenders Harry Maguire and Aaron Wan-Bissaka and winger Daniel James.
“I like the three,” he said. “I think they are bringing some good quality to the team. But the team as a team, I don’t like at all. I’m not surprised by the result and I don’t think Ole can take any positives from the game.”
Former United captain Roy Keane, who won multiple trophies under former boss Alex Ferguson, said it was “scary how far they’ve fallen”.
To make matters even worse for the Solskjaer, England forward Marcus Rashford limped off in the second half, leaving him with no recognised striker on the pitch.
The injury raises even more questions about the decision not to replace forwards Romelu Lukaku and Alexis Sanchez, both of whom are now plying their trade for Inter Milan.
With Anthony Martial out of the picture because of injury, Jesse Lingard came on but looked anonymous as he battles to find form.
But the lack of goals — United have not scored more than once in a game since their opening-day 4-0 victory against Chelsea — is not just due to misfiring forwards.
The midfield looks old, flat and ponderous, a world away from the goalscoring power and creativity that Pep Guardiola’s City boast in abundance.
In the absence of the injured Paul Pogba, Nemanja Matic lined up alongside Scott McTominay, Juan Mata and Andreas Pereira against West Ham in a side lacking pace and ideas.
United also have work to do at the back, despite the summer recruitment of Wan-Bissaka and Maguire at considerable cost.
Maguire is an upgrade at centre-back and has already shown glimpses of the leadership that the club were so sorely lacking last season and Wan-Bissaka has also impressed.
But 34-year-old defender Ashley Young was captain at the London Stadium and it was his scything challenge on Mark Noble that lead to the late free-kick from which West Ham scored their second goal.
Solskjaer did his best to put a brave face on the defeat, saying it hinged on key moments that had gone West Ham’s way.
“It’s a good group to work with,” he said of his players. “They’re determined. Sometimes along the road you’re going to hit some bumps, some highs and lows.”
“This group want to do what we’re trying to do in training,” he added. “It’s key moments in games that can tip these games in our favour… but the attitude and desire is there. That’s not the problem. It’s the quality in our decision-making and sometimes in the execution.”
But the manager who played for United ahead of a midfield of Keane, David Beckham and Paul Scholes will know in his heart that his side do not have the quality to challenge for the Premier League title.
The more immediate problem is that on current form they look unlikely even to make the top four, which would mean another season out of the Champions League.
The season is still young but the clock is already ticking for Solskjaer.