Manchester - Louis van Gaal admitted the furious reaction of Manchester United supporters to their side's dismal 1-0 defeat against Southampton was the worst he has experienced in an increasingly turbulent season.
Van Gaal's side failed to score at Old Trafford for the seventh time this term and were eventually beaten by a late headed goal from Southampton debutant Charlie Austin.
United are now five points adrift of a top-four place in the Premier League and their dejected players trudged off with boos ringing in their ears at full-time.
Inevitably, beleaguered boss van Gaal was also subjected to renewed derision from disgruntled fans who have given the Dutchman plenty of abuse for his conservative tactics over the last few months.
The pressure on van Gaal will only increase with United having won just three of their last 13 games and he accepted the criticism from supporters was more vitriolic than ever.
"Yes, because it was very clear," he said. "I can imagine (why) also because I have seen a poor match.
"I cannot change that feeling. I can only work hard with my players to improve our game and that is what I am doing.
"Of course I am disappointed but I have to think and already I put the question how I can change this because we have to change this.
"That is my job and it's not an easy job at the moment. Nevertheless, we have won three times in 2016 and had a draw, so they were very good results in January.
"But we could not show it in this game. I did not see that confidence today."
Although van Gaal knows his approval rating is at an all-time low with United fans, the former Barcelona and Bayern Munich manager refused to be drawn on whether his job may be under threat.
"I cannot answer that because normally I communicate everything with everybody so it is not for me to answer these kinds of questions," he said.
United are in desperate need of a lift to prevent their season disintegrating even further, but van Gaal could give no guarantees that it may come via a move into the January transfer market.
He has already indicated that he would like to strengthen his defensive options with Matteo Darmian, who he said had gone to hospital for checks after spitting blood following a collision with Southampton striker Shane Long, potentially adding to a lengthy injury list.
But regarding the much-needed arrival of creative talents, van Gaal said: "I think one player cannot change everything. Sometimes it looks like it but it is always the process of team building that makes a team stronger.
"Sometimes one individual can give the first stimulus for that process but it is not so easy as you say or ask."
Southampton manager Ronald Koeman - an old rival of van Gaal from their time together in Dutch football, appears to have managed just that with the capture of Austin, whose goal secured a third straight league win for the Saints.
The 26-year-old is a proven goalscorer but only Southampton were willing to meet QPR's modest £4 million asking price.
"We are very happy we had the possibility to sign Charlie and Charlie was happy to sign for Southampton because he knows Southampton produces good football and gives young players a chance and all the chance to play for their national team," Koeman said.
"That is the reason we liked to sign Charlie Austin - a great numbers of goals. With Shane together in the last 10-15 minutes they did a great job but it is not fair to mention one player.
"It was a great win. I think it was a difficult game for both teams today. We knew they are under pressure and if you keep the organisation in your team, they will be nervous."