Jose Mourinho believes Manchester United lost focus after the mistakes that set his side on course for a shock 3-2 defeat at Brighton and Hove Albion.
United were poor defensively in the first half on Sunday and conceded twice in quick succession to Glenn Murray and Shane Duffy, before Eric Bailly gave away a penalty on the stroke of half-time after Romelu Lukaku's goal had given the visitors hope.
And Mourinho revealed it was difficult to lift his side at the break as United's confidence was severely damaged by the hapless showings of Bailly and defensive partner Victor Lindelof.
"There were too many mistakes and we were punished for the mistakes. Sometimes teams make mistakes and you are not punished," Mourinho told Sky Sports. "We were always punished for every mistake we made.
"At half-time we tried; in the second half we tried. But from a mental point of view, the accumulation of the mistakes and the punishment of the mistakes with goals was giving confidence to a good team like Brighton, and took that confidence from us.
"I was not expecting these big mistakes - we are not talking about small mistakes - and we were punished by these big mistakes.
"You lose your confidence, there is a tendency to lose the direction of the game plan. We came here with an intention and then suddenly you are losing 2-0.
"You score the first goal and you think let's go to the second half at 2-1, on a high, and then suddenly you make that mistake and concede that goal. You go to half-time in a situation where the players are really, really, really down."
The United boss was reportedly frustrated by the inability to sign a centre-back in the off-season, but he refused to discuss transfer window failings on Sunday.
"The transfer window opens on January 1," he said. "It's closed."
And Mourinho would not criticise his players, believing that he would receive unfavourable media coverage after alleged disputes with the likes of Luke Shaw and Paul Pogba.
"When I speak about individual performances and I'm critical about my players, you do not accept it," he said.
"The press, the pundits are usually very critical of me when I go in that direction. Please do not ask me to go in this direction. It's not good for me.
"I will be very, very happy to analyse my players' performances when the performances are very good. It's a great thing for me to come in front of the cameras and say players A, B, C put in fantastic performances.
"When I cannot do that, don't push me to the other side. I do not go to the other side."
|Can apologises following sexism accusations|
|De Bruyne expects to be back for Manchester derby|
|Celtic 1 Rosenborg 0: Griffiths late show lifts Hoops|
|Woods eagles 18 to make 65 at Tour Championship|
|Arsenal 4 Vorskla 2: Aubameyang at the double in entertaining triumph|
|Dudelange 0 AC Milan 1: Deflected Higuain goal spares Gattuso´s blushes|
|Birthday boy Rashid inspires Afghanistan to Asia Cup win|
|Sarri feeling sorry for ´unlucky´ Morata|
|Ryder Cup pick Garcia shoots 66 at Portugal Masters|
|Ronaldo, Zidane, Cantona and the most infamous red cards|
|Villarreal 2 Rangers 2: Arfield and Lafferty steal point for Gerrard´s men|
|PAOK 0 Chelsea 1: Willian strikes as Morata misfires|
|Rain delays Ostapenko in Seoul, Wang books Guangzhou semi|
|Pochettino backs Kane to end goal drought|
|We figured it out - 76ers´ Markelle Fultz rebuilds jump shot|
|Joshua: Povetkin my second-toughest fight|
|Relaxed Pochettino not pushing panic button|
|Why Manchester City fans must fix their relationship with the Champions League|
|Majestic Giorgi ends Wozniacki´s reign in Tokyo|
|Pochettino unwilling to risk Alli fitness|
|Bigger Champions League tests to come, warns Pogba|
|Eight for 10! - Nadeem spins his way to world-record figures|
|A 4-1 lead cut to 3-2 by VAR, but Quakes have no complaints after Atlanta defeat|
|UEFA opens disciplinary proceedings against Ronaldo|
|Joshua v Povetkin: Recapping AJ´s previous world title defences|
|Players told to ink twice over showing tattoos at Rugby World Cup in Japan|
|Mariano targeting Spain call-up after goalscoring Madrid return|
|Pandya, Axar and Thakur out of Asia Cup|
|England omit Cipriani, Tuilagi and Ashton called up|
|Can reacts to Ronaldo´s red card: We are not women|
|One Year to Go: Five Rugby World Cup debutants set to shine|
|Shy Osaka not comfortable with new-found fame|
|Belgium and World Cup winners France make FIFA rankings history|
|Ronaldo wanted to impress - Bernardeschi sympathises after Juve superstar´s red|
|Van Dijk warns Liverpool: Believe we can win trophies or stay home|
|Menezes complains of anti-Brazilian conspiracy after Dede´s VAR red|
|Diamondbacks rout Cubs to remain in postseason picture|
|Modric embraces Ballon d´Or chants as Di Francesco backs Madrid star for award|
|MLS Review: Martinez helps Atlanta stage comeback amid VAR controversy|
|Kerevi recommits to Wallabies, Reds|
|Lyon to ban fan for life after footage of Nazi salute emerges|
|Milan must respect opponents – Gattuso not underestimating Dudelange|
|Copa Libertadores Review: Zarate leads Boca, River draw|
|Mourinho: Dalot can play at Man United for more than 10 years|
|Johnson hoping to erase East Lake demons|
|´No question´ Fitzgerald faces Bears, says Cardinals´ Wilks|
|Rodgers says roughing the passer penalties are ´going the wrong direction´|
|Ravens fined $200,000 for violating communication policy|
|LeBron James set to star in ´Space Jam´ sequel|
|Ronaldo red card ´absurd´, says Pjanic|
|Kovac hails ´special´ Sanches after Bayern goal|
|Marcelino: Tearful Ronaldo said he did nothing wrong|
|Fernandinho takes blame for Man City´s Lyon loss|
|Lovren denies any wrongdoing after perjury charge|
|Plzen boss Vrba slams late mistakes|
|I almost scored as many as Messi - Tagliafico the unlikely hero for Ajax|
|Ronaldo deserves Ballon d´Or not Modric, says Casemiro|
|United fan Rafael - I´ve never lost at City|
|Davis explains abrupt mid-game NFL retirement: ´Football is not for me´|
|Lopes pays tribute to under-fire Lyon coach Genesio|
|Toulon´s Bastareaud handed five-week ban|
|Steelers WR Brown disciplined for missing meeting|
|Arteta refuses to make excuses for Manchester City´s Lyon loss|
|Allegri calls for VAR after Ronaldo´s contentious red card|
|Championship Review: Boro go second, Birmingham still winless|
|Lopetegui: Mariano took his chance|
|Juventus proved their quality after Ronaldo red card - Bonucci|
|Pogba ´class´ impresses Mourinho|
|Man City not Champions League favourites, insists Bernardo Silva|
|Isco calls for Modric to win Ballon d´Or after Champions League win|