Here come the players for part two. Manchester United will want to kill this quickly. The longer it stays 1-0, the more nervous they - and the home fans - will get.

Saying that, West Ham have to offer a lot more than they did first half.

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Anurag: Matic appears like a sorcerer on the pitch. Such trickery not seen on Old Trafford since Scholes and Giggs at their best. Brilliant signing.

Latex Zebra: £75 million for a goal, at home, against West Ham. When he bangs in three against Chelsea, then it's money well spent.

Andy: David Gold promised we'd be competing with the big clubs by now, thanks to the Olympic Stadium. This shows how far away we are.

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Simon Stone
BBC Sport at Old Trafford

I couldn't have been more impressed with Nemanja Matic in that first-half.

The former Chelsea man was an effective screen for Manchester United's defence, is unfussy with his passing, and he also gets forward.

Marcus Rashford gets the assist for Romelu Lukaku's goal but without Matic's unselfish run on his outside, the England forward probably does not get the space to cut inside to unsettle the visitors defence.

Chelsea have taken a bit of a risk letting Matic join a major title rival.

Robbie Savage
Ex-Leicester City & Wales midfielder on Radio 5 live

I think Nemanja Matic has been absolutely outstanding in this first half. Everything he does is neat and tidy. He protects Phil Jones and Eric Bailly so well. When they counter-attack they have so much pace and power going forward. It has been very good to watch.

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Jonathan Overend
BBC Radio 5 live

What a really enjoyable half of football. Some ferocious tackles going on, Martin Atkinson refereed the half really well and there was no shortage of skill. The skill on display reminds you of the level we are privileged enough to be watching.

Excitement. Excitement is back at Old Trafford, isn't it?

Manchester United will be happy with this. They have absolutely dominated the game and lead through Romelu Lukaku's debut goal.

The only criticism is a familiar one - they should lead by more.

West Ham need a serious half-time re-think.

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Oh, good save! It is the sign of a great keeper that he can make a save when required after having not seen the ball for a good 45 minutes.

West Ham - in their best attack of the game so far - open the home side up and present a shooting chance for Andre Ayew. He strikes it well from the edge of the box but David de Gea is right behind it and palms it away.

John Murray
BBC football correspondent

The style of play has been exciting. There is so much talent. The Manchester United fans are onto Joe Hart in terms of footwork and his distribution. Manchester United's bench is an indication of the strength of the players they have, without any new players.

Eric Bailly goes into the book for a foul on Javier Hernandez, but the ref makes it clear that it is for an accumulation of fouls in this first half.

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Robbie Savage
Ex-Leicester City & Wales midfielder on Radio 5 live

We have seen it so many times last year that Manchester United got the first goal and did not get anything else. When it is 1-0, teams coming to Old Trafford will always fancy a draw. It is important I think, this season, when Manchester United go 1-0 up here to get a second goal as soon as possible.

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Kunal Gupta: Absolutely loving Matic. Cannot believe Chelsea sold him to us. Absolutely buzzing.

Gareth Newman:Purchase of Matic supposed to free up Pogba to show how good he is? More likely to show how overrated he actually is.

Phil Johnson: United dominating possession, but have one shot on goal. So how is this different than last year?

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Manchester United are enjoying themselves. Nemanja Matic is even pulling out a skillful dribble to see off a West Ham man on the right touchline.

He's winning himself a lot of new fans, the ex-Chelsea man.

Hammers fans must be sick of the sight of Romelu Lukaku...

Tom Fisk:Three certainties in life. Death. Taxes. Lukaku scoring against West Ham.

Lotak: What a ball from Marcus Rashford. Inch perfect. Could be a very lethal partnership if they have that sort of understanding.

Sophie Gayter: What a brilliant goal. Great play from Matic, great ball from Rashford, great finish from Lukaku. Get in.

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Rashford played a key role in that goal. Yes, the pass for the assist was good, but it was his driving run through the heart of the West Ham midfield that had the Hammers on the back foot.

Robbie Savage
Ex-Leicester City & Wales midfielder on Radio 5 live

Fantastic play. Pablo Zabaleta was out of position. That allowed Marcus Rashford to run at the defender. Romelu Lukaku made a diagonal run. The timing of the pass from Marcus Rashford was fantastic. Great finish, great counter attack.

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All the ball, all the territory... but still no goals. Sound familiar Manchester United fans?

Image source, Opta

Robbie Savage
Ex-Leicester City & Wales midfielder on Radio 5 live

At times West Ham are playing six at the back with Mark Noble and Edimilson Fernandes in there. They just cannot get near Nemanja Matic and Paul Pogba. They cannot get out. They have all dropped out until it gets to their final third and they become very compact.

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When you get so few chances to make any kind of impact in the opposition's half you need to make the absolute most of them. Marko Arnautovic's free-kick towards the home box, which is headed simply away by a Manchester United defender, doesn't cut mustard.