Doubles from Kevin De Bruyne and Riyad Mahrez restored City's six-point lead at the top of the Premier League as the champions delivered a commanding performance at the Etihad Stadium.

Jadon Sancho had equalised in the first half for United, but City soon showed their dominance and after De Bruyne's second goal restored the hosts' lead, the result was never in doubt.

• Man City 4-1 Man Utd - Match report and highlights
• Manchester derby ratings: De Bruyne masterclass as Wan-Bissaka struggles
• How the teams lined up | Match stats
• Watch PL highlights for free on Sky Sports

"Manchester United's response to going 3-1 down has been embarrassing. Ninety-two per cent possession for City? They have given up," Sky Sports pundit Neville said. "They are walking around the pitch. It's nowhere near good enough.

"There can be no complaints. City have been absolutely outstanding. But as a Manchester United fan, it's embarrassing.

"City played brilliantly in the second half. But the effort and intensity from United in the last 20 minutes was non-existent.

"The scoreline isn't the problem. It's the response to going 3-1 down that's the problem. They have thrown the towel in.

"At the end of the game, Manchester United finished like an absolute shower. They were a disgrace in the last 25 minutes."

Keane: 'Man Utd were shameful'

Keane agreed with Neville's withering assessment, describing United's response as "shameful".

"The worst thing that you could say about United is that they gave up," Keane told Sky Sports. "In any game, if you give up, it's unforgivable really. The beauty of top-level sport is that there's no hiding place.

"I know United have done well there in the last few years, but we saw all of United's shortcomings today. Man City were very good in the second half, but there are ways to lose football matches.

"You've got players not putting in performances and players not running back. They stopped running and they gave up. I don't understand it.

"The manager will be criticised about his tactics, but players not running back when you're playing for Man Utd is really unacceptable.

"They threw the towel in which is shameful. You need character and personality when you're up against it and after the third goal, it was game over."

Keane: Five or six players shouldn't play for Man Utd again

Keane continued by arguing United's performance was so poor that "five or six players" should never play for the club again.

"You've got to run back and you've got to tackle. United players have shown quality over the years but we've seen a reflection of where the team is and where the club is," Keane added.

"They're so far behind the other teams. You hear noises all the time about things going on in the dressing room with a new manager coming in, but your own bit of pride eventually has to kick in at some stage.

"There were five or six players there who should never play for Manchester United again. It was shameful.

"City are a fantastic team and that's why they are champions. You hoped the subs who came on would have an impact, but they're not prepared to run around, couple of lads in midfield, Wan-Bissaka, Fred, Maguire, Rashford, I could go on.

"City didn't have to be at their best. They still had another couple of gears to go. They toyed with them like they did at Old Trafford.

"It was men vs boys as the old saying goes. They gave up and shame on them.

"United's history has been built on character and personality when you're up against it. I feel like I've been sat here for two weeks.

"United were never going to get back into it. The white flag came up and the game was over. It was unthinkable."

How poor were Manchester United in the second half?

Manchester United created an xG of 0.00 against Man City in the second half of Sunday's derby.

They failed to produce a shot of any description, had just four touches of the ball in City's box and secured only 21% of possession.

Keane: Ronaldo injury doesn't add up

Before kick-off, United interim manager Ralf Rangnick confirmed Cristiano Ronaldo was ruled out of the game due to a hip injury, but Keane believes something about the forward's absence "doesn't add up".

• Rangnick: Ronaldo has hip problem | Keane: It doesn't add up

He had earlier said: "There seems to be more to the Ronaldo story when a manager comes out and talks about a hip flexor. I don't get it. We talk about Ronaldo being a machine and very rarely getting injured but every now and again he comes out with that... a hip flexor? It doesn't add up to me."

After the match, Keane added: "The Ronaldo stuff before the game worried me. There's something going on in the background with the club, the team and the players.

"There's something really amiss and we've been saying this for months now. There was no hiding place today and it was hard to watch."

Redknapp: 'Man Utd a million miles off'

Fellow Sky Sports pundit and former City defender Micah Richards agreed with Keane's view that it was "men vs boys" in the second half, while Jamie Redknapp insists United are "a million miles off" challenging for the title.

"I don't feel these City players feel the pressure. They know about the quality of Liverpool but they've turned up today and they've done the business," Richards said.

"It was men versus boys in that second half. Give praise to Manchester United at half-time as they did well up to that point, but in the second half they just took the game to a different level. When Kevin De Bruyne plays like that, he's the best midfielder in the league.

"The City team are relentless and if they turned up today they would win. They're just better."

Redknapp said: "There's a massive gulf between the two sides. What City have done over the past 10 years is they've created a team and they've thought about signings. With United, they've thrown together a team and they've hoped it's going to work.

"They've spent £50m on a right-back in Aaron Wan-Bissaka and there's been no improvement since he's been there.

"The other full-back, there's been no improvement. At centre-back they can't find a pair, in midfield they're not good enough and going forward they played with Pogba and Fernandes up front and it didn't work.

"As a team, it's not working. It takes time and needs the right culture. Right now, United are a million miles off.

"Whoever comes in next is going to need so much time and so many things to go for him. If you were Jurgen Klopp or Liverpool players watching that, you'd be fuming. They didn't even try a leg in the second half."

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