John Dunthorne: Ah, one of those games when the defences do not turn up. Great.

Liam Stones: Ashley Young still couldn't stay on his feet even when he's scoring!

Bunmun: Wow, anything can happen in this Manchester derby. Jones and Smalling don't look comfortable.

United had not been at the races but they're level now and the home crowd smell blood. Crystal Palace striker Glenn Murray had a field day against this City defence last Monday and they haven't dealt with any direct balls down the middle yet. Marouane Fellaini could be a weapon for United today.

Image source, Reuters

BBC Sport pundit Robbie Savage at Old Trafford

"What a game! Gael Clichy got a block in on Ashley Young, but the ball fell fortunately for the United man and he was quickest to react. It's a really open game so far."

Image source, AP

Route one! This is rubbish defending as United level in Sunday League style. David de Gea lumps it downfield, Ander Herrera puts in an early cross and the City defence are all over the place. The ball hits Gael Clichy on the back and drops for Ashley Young, who swivels sharply to slam into the open net.

Lovely finish.

Image source, AP

Phil McNulty
BBC Sport chief football writer

"Manchester City hit Manchester United with a whirlwind start here last season and scored early through Edin Dzeko. This is no different and Sergio Aguero's goal had been coming from the first whistle.

"It has been a devastating opening burst and Louis van Gaal's side need to clear their heads here. City fans exultant and Manuel Pellegrini in his technical area demanding even more players move forward. The normally understated Chilean pumped his fists in delight when Aguero scored in front of the Stretford End."

The home side have been totally off the boil in the opening stages. They have had one wake-up call.

Boos around the ground as Gael Clichy escapes a yellow card again - that's two tackles which could well have been bookings avoided.

Image source, Getty Images

Andrew Morris: City all over United and that goal has been coming. United at sixes and sevens. United are in for a long day.

Samo Alfred: Man City will vent their anger on Man Utd. Said that a week ago. It just started!

Shohidur Rahman: Shocking start, absolutely shocking. United need to wake up.

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Manuel Pellegrini dialled up his celebration to 11 for that opener. Normally a man of few emotions, he gave that the big one. This is a very important game for the Chilean.

All City so far.

BBC Sport pundit Robbie Savage at Old Trafford

"Well you have to stay great play from Manchester City, but there was so much miscommunication between Michael Carrick and Juan Mata. Neither player picked him up. It's poor defending and Sergio Aguero was unmarked to tap in. They've probably deserved the lead."

Image source, Reuters

Surgical. City dissect United easily and score a wonderful goal. James Milner finds David Silva on the left of the area, he looks up and picks out Sergio Aguero for a tap-in inside the goalmouth.

Some textbook ball-watching from Phil Jones there. No appreciation of what - or who - was behind him. A deserved lead.

Image source, Getty Images

Fernandinho with a crunching tackle in midfield - that's got the game going. Good spell for City.

BBC Sport pundit Robbie Savage at Old Trafford

"That's where Manchester City can exploit United in wide areas, but Jesus Navas needs to show more confidence with his finish there."

A great chance for the visitors! It's route one stuff, a clearance from defence and Jesus Navas breaks the offside trap to skin Daley Blind, He powers into the box but has to shoot from a tight angle as there's no support. De Gea blocks it solidly at the front post.

City on top - and Michael Carrick has to make a great tackle to stop Yaya Toure sweeping in the corner.

David Silva with a wonderful ball down the left to find Sergio Aguero but Chris Smalling does well to shut him down. Yaya Toure gets the ball 30 yards out but decided not to shoot. Worth a go in these conditions.

BBC Sport pundit Robbie Savage at Old Trafford

"A very nervous start from Manchester City, giving the ball away in dangerous areas. But Joe Hart is a picture of calm in goal behind them."

Joe Hart on his toes to stop Wayne Rooney latching on to a loose ball, fine goalkeeping.

Before the game Manuel Pellegrini said that James Milner 'can play up front' and he is very close to Sergio Aguero in the opening stages. David Silva is left of midfield, I expected those two to be the other way around. Gael Clichy wit the first reducer of the day - he avoids a yellow card though.

City get the game up and running, great noise inside the stadium.

I'd imagine it has been a while since United fans looked forward to derby day. Are they favourites? Neither manager would admit so before the game...

Alex Haworth: Haven't looked forward to a Manchester derby this much for years. I'm confident that King Louis can mastermind another big win.

Sonny ‏Charles: A Manchester United fan, but couldn't see a single one of our defenders making that combined Manchester team.

Richard Elliott: Massive test for Kompany. He's prone to over-committing in the big games and I fear this time will be no different.

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