Joe Hart bemoaned one of his 'worst days in a Manchester City shirt ' following Sunday 's derby thumping by Manchester United . The England number one appeared devastated after the final whistle at Old Trafford and acknowledged that City 's bid to retain their Premier League title was over . 'That 's one of my worst in a Man City shirt , definitely , ' Hart said after a morale-sapping 4-2 defeat saw under-fire Manuel Pellegrini 's men go four points adrift of neighbours United and 12 behind runaway leaders Chelsea . Manchester City goalkeeper Joe Hart , pictured with Frank Lampard , was disappointed with his side 's display . Hart was unable to keep out goals by United 's Ashley Young , Marouane Fellaini , Juan Mata and Chris Smalling . Manchester City are four points behind rivals United . The 27-year-old has even given up on knocking Arsenal out of second place . 'It 's essential to try and finish third , ' he added . 'We 've got to get our heads down and win these massive games . ' City had looked dominant in the early stages , racing into a 1-0 lead that they could have extended before Ashley Young 's equaliser triggered a derby demolition . 'Not many teams have put us to the sword like that , ' Hart said . 'United know what they are doing , they took their chances . Hart , pictured saluting the travelling City fans , does not understand why his side are struggling for form . 'It 's hard to take . We 've won enough of them to know how to lose properly though and we were n't good enough after the first 15 minutes . ' Hart added that City had let their fans down and revealed he was at a loss to explain a dramatic loss in form since the turn of the year that has seen them take 18 points from a possible 39 . 'It would be easier to win games if I knew what was wrong with us but we 've played well and been unfortunate in some games , ' he said . ' I 'm hurting from this defeat . There 's a lot of emotion running through me . Let 's see how it feels on Monday , we 'll think about it and we 'll go again . '
Joe Hart conceded four goals in Man City 's 4-2 defeat at Arsenal . The Man City stopper appears to have given up on trying to catch Old Trafford . Hart said after Sunday 's defeat that 'it 's essential to try and finish third ' READ : Gloves on April 12 ? ! Man City players feel the derby day cold . READ : Ashley Young laughs at City as United silence 'noisy neighbours '