David Moyes branded Manchester United's defending "terrible" and "stupid" following their 2-0 loss to Everton on Sunday.
The Scot suffered a miserable first return to Goodison Park, as a Leighton Baines penalty and Kevin Mirallas' narrow strike handed Everton a comfortable victory.
Baines tucked away the 28th-minute spot-kick after Phil Jones had inexplicably handled Romelu Lukaku's shot, and Moyes was left distinctly unimpressed by his side's defensive showing.
"We gave away two terrible goals," he told Sky Sports.
"We get done by two stupid decisions - well, a stupid decision to dive in front of the ball in one of them.
"Prior to that we had passed the ball well, kept it well, and were in control of the game.
"We played well in the first half, but didn't have a final through-pass or a final finish, that was the disappointing part."
The defeat means it is now mathematically impossible for United to reach the top four and a spot in next season's UEFA Champions League.
Moyes confirmed the blow would be painful to take, but insisted work is going on "behind the scenes" to improve his squad ahead of next season.
"It does (hurt), because it's part of this club and we want to be in it," he said.
"We want to get back in it as quickly as we can.
"We're going to try to get a team that can win better than this team can."
|Coach: Roberto Martínez|
for S. Distin 46'
for R. Barkley 70'
for K. Mirallas 90+4'
|Shaw going through ´difficult period´ - Mourinho|
|Klopp not worried by Sturridge, Origi form|
|De Gea backs ´amazing´ Pogba|
|Pochettino: Tottenham bigger than City|
|Conte: I trust Diego Costa 100 per cent|
|Lewandowski admits he was lucky for Bayern winner|
|City as sharp as Barca and Bayern but lacking consistency, says Guardiola|
|Nice go top but struggles continue in draw with 10-man Bastia|
|AC Milan pull Deulofeu Tweet amid reports deal not yet complete|
|New Manchester City deal for Aguero but little fanfare|
|Matip gets all clear from FIFA to play for Liverpool after Cameroon row|
|Freiburg 1 Bayern Munich 2: Lewandowski to the rescue with late winner|
|Fonte completes £8million West Ham switch|
|Morocco 3 Togo 1: Renard´s men back on track with comeback victory|
|Stoke complete £12million Berahino signing|
|Egypt v Uganda: Pressure on Pharaohs to kickstart campaign|
|Aspas responds to alleged Ramos spit|
|Stoke agree Berahino deal with West Brom|
|AC Milan complete Deulofeu loan signing|
|Gerrard returns to Liverpool as academy coach|
|Ivory Coast 2 DR Congo 2: Serey Die rescues point but holders still in trouble|
|Di Maria committed to PSG amid reported CSL interest|
|Sanchez a role model - Xhaka|
|Tuchel trusts Schurrle to fill Aubameyang void|
|Ghana v Mali: Rahman injury poses a problem for Grant|
|Depay not holding Manchester United grudge|
|I love watching them - Guardiola a huge fan of Pochettino and Tottenham|
|Klopp: I could kick Mane in the... lower back|
|Conte: Ake is ready to help Chelsea´s title bid|
|Allardyce provides Evra, Van Aanholt and Jenknson updates|
|Guardiola looks beyond beleaguered Bravo for City woes|
|Begovic could leave Chelsea - Conte|
|PSG still on the hunt for striker, says Emery|
|Mourinho: Valencia the best right-back in football|
|Mourinho on Young to China talk: He hasn´t told me anything!|
|Costa wants to stay at Chelsea, reveals Conte|
|´I played worse sometimes´ - Zidane defends Ronaldo from critics|
|Injured Iniesta to miss Eibar clash|
|Mourinho open to Depay return|
|Lyon confirm Depay arrival|
|Germany to bid for Euro 2024|
|Sydney FC 2 Adelaide United 0: Two goals in three minutes extend lead|
|Depay could face Marseille as Lyon boss Genesio hails winger´s ´big motivation´|
|Hull loan Elabdellaoui from Olympiacos|
|AC Milan make final offer for Deulofeu|
|Hughes ´wouldn´t encourage´ Bojan bids|
|Worker dies at World Cup stadium in Qatar|
|West Brom sign Livermore|
|Lyon president Aulas: Depay deal imminent|
|Aubameyang: I could leave Dortmund, but I´d never join Bayern|
|´Equating Messi with anyone else is like comparing a policeman with Batman´ - Sampaoli|
|It will take years to build football culture, Wenger warns CSL|
|´Worried´ Rakitic wants Barca renewal|
|Inter not signing Messi - Moratti|
|Luis Enrique hails Barca defence after ending Anoeta curse|
|´He is made of different stuff´ - Spalletti hails Nainggolan after wondergoal|
|Tottenham´s Janssen turned down Galatasaray move, agent claims|
|Did Carroll´s wondergoal give the West Ham striker whiplash?|
|Iniesta suffers calf injury|
|Swansea situation not ´hopeless´, says Clement|
|Real Sociedad 0 Barcelona 1: Neymar ends Anoeta curse|
|´Immeasurable bulls**t´ - Ligue 1 coach destroys Van Basten´s offside plan|
|Simeone praises Atletico´s precision in Copa Del Rey win|
|Fonte situation difficult for Southampton - Puel|
|´Some of the best football in the UK´ - Watford´s Mazzarri hails Bournemouth|
|Senegal 2 Zimbabwe 0: Cisse´s men charge into quarter-finals|
|Rivaldo backs Luis Enrique to deliver more Barca success|
|Atletico Madrid 3 Eibar 0: Routine win earns quarter-final lead|
|Jesus will make Premier League history - Rivaldo|
|Adebayor: Arsenal are just Ozil and Sanchez|
|Algeria 1 Tunisia 2: Favourites on brink of elimination|
|Bayern keen to seal Coman deal as Rummenigge cools Gnabry interest|
|Pochettino has done his homework on Jesus as Spurs look to march on|
|Scrap offside? Premier League managers give Van Basten´s plans a cool reception|
|Coman ready for Bayern comeback, confirms Ancelotti|
|Pochettino upbeat despite six weeks out for Vertonghen, Lamela still a mystery|
|Cerezo defiant over Griezmann amid talk of Manchester United agreement|
|Robinho named in Brazil squad for Chapecoense fundraiser|
|Davies and Lookman aren´t the big men of Everton, warns Koeman|
|Ivory Coast v DR Congo: Dussyer demands champions show true strength|
|Replacing Robben and Ribery not easy - Hitzfeld|
|Yeray back in Athletic training after successful cancer surgery|
|Karanka targeting more Boro deals after Bamford swoop|
|Cavani: I am the ultimate finisher|
|Morocco v Togo: El Ahmadi hungry for success|
|Ancelotti denies Verratti approach|
|A-League Review: Cahill double sees Melbourne City sink Mariners|
|Manchester United very happy with Shaw, insists agent|
|Mertesacker extends Arsenal deal|
|Boost for Arsenal as key quartet returns to training|
|Will Jesus save Manchester City´s title bid? Guardiola´s new striker in Opta numbers|
|Tevez mobbed after touching down in Shanghai|
|Payet exit not inevitable - Bilic|
|Wenger: Arsenal don´t need Payet|
|Jesus wants Manchester City titles|
|Orsolini arrives for Juventus medical|
|Rivaldo backs Coutinho to join Neymar at Barcelona|
|No danger of Messi leaving Barcelona, says father|
|Augusto: I convinced Oscar to come to China|
|Madrid-bound Maradona visits Napoli training|
|Sevilla in no rush over Sampaoli talks despite Barcelona links|
|Cafu: Resurgent Brazil can challenge world´s best|
|Klopp thrilled with Coutinho|
|Manchester United replace Real Madrid as world´s richest club|
|Madrid squad annoyed by defeats - Zidane wants more energy after latest loss|
|Casemiro rues more misery for Madrid against Celta|
|´Job done, let´s go home´ - Klopp happy to avoid extra time with narrow Plymouth win|