Thomas Frank slammed the Tottenham fans who booed Guglielmo Vicario after the goalkeeper's howler condemned his side to a dismal 2-1 defeat against Fulham on Saturday.
Frank's side made a disastrous start as Kenny Tete put Fulham ahead before Harry Wilson's superb strike punished a calamitous blunder from Vicario.
Vicario was barraged with jeers from furious Tottenham fans as soon as he touched the ball in the immediate aftermath of the goal.
Tottenham were booed off at halftime, and although Mohammed Kudus pulled one back after the interval, there were more taunts at the final whistle.
"When you're in a bad spell, everything seems to go against you. The second goal is a mistake from Vic. I didn't like that our fans booed at him straight after and a few times after that," Frank said.
"They can't be true Tottenham fans because everyone supports each other when you're on the pitch and we do everything we can to perform.
"It is OK that they are frustrated, because we haven't won at home for a long time. We all badly want to win, so I'm fine with them booing after the game, but during the game, I hope it was one incident and it never happens again. That is unacceptable in my opinion."
VICARIO APOLOGY
Apologising for his error, Vicario said: "The second goal was a mistake of mine. I take the responsibility for that. The intent was to clear the ball long, but I hit the ball in a bad way.
"The booing is part of football. I'm a big man. I'm quite old. We cannot be influenced by situations in the stand. Fans have the right to do what they think.
"We apologise for the defeat. It's painful."
Tottenham defender Pedro Porro appeared to make an angry gesture towards the supporters while walking off the pitch and Frank added, "I didn't see the incident, so I don't know exactly.
"We are in a tough spell right now and for my players, it is about being as calm as possible and doing everything we can to work through it."
With only three wins in their last 13 games in all competitions, Tottenham have slumped to 10th place in the Premier League.
Frank insisted this week that he was confident that Tottenham's home form would eventually "click", but they have just three league victories in north London in 2025.
Tottenham are without a Premier League home victory since the opening weekend of the season, winning only four of their 10 matches in front of their fans in all competitions this season.
Tottenham's 4-1 loss at arch rivals Arsenal last weekend and a 5-3 defeat away to Paris Saint-Germain in the Champions League on Wednesday had added to the pressure on Frank to end their home woes.
FRANK UNDER FIRE
Fulham had picked up just one point away from home this season while losing their previous five, making them appear the ideal opponents for Tottenham to get back on track.
Instead, a third successive defeat left former Brentford boss Frank facing pointed questions about his ability to make a bigger impact than his predecessor, Ange Postecoglou.
The Australian was sacked despite winning the Europa League last season to end Tottenham's 17-year trophy drought.
Tottenham did nothing to help Frank as they shot themselves in the foot twice in the first six minutes.
They fell behind in the fourth minute when Samuel Chukwueze's pass found Tete in acres of space on the edge of the area and the unmarked defender drilled a low strike that deflected in off Destiny Udogie.
Two minutes later, Frank's misery was compounded as Vicario needlessly rushed out of his area and made a hash of clearing the ball, giving Wilson the chance for a sublime strike that curled into the empty net from wide on the right flank.
Kudus reduced the deficit in the 59th minute, deftly controlling on his thigh before lashing a superb strike into the top corner from just inside the area.