Gary Neville tore into Manchester City following their defeat against Crystal Palace by insisting the champions have a 'mentality problem' which prevents them from winning back-to-back titles. The former Manchester United and England defender saw City lose 2-1 to leave them in fourth - nine points short of Chelsea at the top of the Barclays Premier League. 'They've got a mentality problem. There's no doubt,' Neville said on Monday Night Football. 'This team cannot sustain success. Manchester City captain Vincent Kompany leaves the field after their 2-1 defeat by Crystal Palace on Monday . Manuel Pellegirni is under pressure as City fell nine points behind Chelsea in the Premier League table . How the top of the Premier League table looks . 'When you win championships, you've got to be able to come back again and show the same hunger. They don't. They drop off it. They get to the top of the mountain and go, "phew, we did it", and it's the worst thing that can happen.' 'They are falling well short of where they should be. Make no mistake about that. It's now or never for this team. They can't progress beyond the knockout stages or the last 16 of the Champions League. 'They can't sustain success by winning back-to-back championships. They're getting older. Their average age is the highest in the league at 29 and a half. Unfortunately some of those lads not going to be there next season. They're going to pay for what is a disappointing season, it is looking like now. 'They're going to get into the top four but that Manchester City team with the ambition that they have got and with the quality they should be doing a lot better.' Gary Neville tore into  City following their defeat by insisting the champions have a 'mentality problem' Ex-Manchester United star Neville was on Monday Night Football with Sportsmail's Jamie Carragher (left)
Manchester City lost 2-1 against Crystal Palace on Monday night . Gary Neville: 'They've got a mentality problem. There's no doubt' Former Manchester United and England defender Neville on what is wrong with reigning champions City: 'This team cannot sustain success' JAMIE CARRAGHER: Yaya Toure ducked out of his duties in the wall . CLICK HERE for all the latest Man City news .