Manchester United's season is in danger of imploding after a 1-0 loss to West Ham on Sunday due to a major goalkeeping error by David De Gea.
The Hammers seem to be secure from relegation, whereas United, who were once strong favorites to finish in the top four of the Premier League and earn a spot in the Champions League for the next season, are now in serious trouble.
De Gea made a disastrous first-half blunder that determined the outcome, allowing a soft effort from Said Benrahma to slip past him in the 27th minute, after his side had mainly controlled the first half.
De Gea's error occurred the same day that he passed Alex Stepney to become the Manchester United goalkeeper with the most appearances (540).
In their midweek loss at Brighton, United, who were hurt by a last-second penalty, had been encouraged by Arsenal's 2-0 victory against third-place Newcastle earlier in the day.
They still have a game in hand but, despite being in fourth position, they are currently only ahead of Liverpool by one point.
This week's Europa Conference League semifinal opponent West Ham sits seven points above the relegation zone.
In east London, David Moyes's Hammers got off to a strong start, putting United on the back foot before the visitors launched a quick counterattack that resulted in Marcus Rashford's missed shot.
Bruno Fernandes and Antony both came close as United gained momentum.
through the 17th minute, as the visitors kept trying to get a foothold, Rashford cut through from the left and struck the outside of the post.
– De Gea mistake –
Benrahma's errant long-range drive, though, eluded De Gea's diving arms and gave West Ham the lead against the flow of play.
The Spaniard seemed to have it under control, but his footwork looked off, and even though he got a touch on the ball, it was not powerful enough to keep it out.
He was unable to process what had occurred as he lay still on the grass while West Ham celebrated.
De Gea has had a mixed season; he is now in the lead for the golden glove award for the Premier League's most clean sheets, but he has also made several expensive mistakes.
In the 32nd minute, United struck the post once again as the vivacious Antony's strong shot was diverted behind the goal.
Erik ten Hag's club managed 11 shots in the first half, but just one of them found the target. Their 49 goals this season are the second-lowest total among the top nine teams.
As the clock approached halftime, De Gea stopped Benrahma a second goal before referee Peter Bankes rejected a huge penalty demand for handball against Victor Lindelof.
In the first few seconds of the second half, De Gea stopped Tomas Soucek's attempt at the near post. Moments later, West Ham had the ball in the goal once again, but the referee whistled for a foul on De Gea by Michail Antonio.
Every time the home team applied pressure, United was shaking terribly and seemed unstable at the back.
With fewer than 20 minutes remaining, Soucek headed the ball into the goal, but the goal was disallowed for offside.
United realized they had to go all out, so Ten Hag substituted Anthony Martial for the unproductive Wout Weghorst and put on Jadon Sancho and Marcel Sabitzer.
However, despite having solid possession for long stretches of time, they seemed to be mainly unsuccessful in attack.
At the beginning of the eight minutes of stoppage time, Martial broke through, but Lukasz Fabianski palmed away his attempt and United ran out of time.
