Match ends, Arsenal 0, Manchester City 2.
Manchester City boss Pep Guardiola says his side will get even better as they deservedly beat Arsenal on the opening day of the Premier League season.
The Gunners were playing their first competitive game without Arsene Wenger in charge since 1996 but were well beaten by the defending champions.
Raheem Sterling put City ahead in the 14th minute when he got the ball on the corner of the box, cut beyond two players and rifled home from 20 yards.
Riyad Mahrez went close to scoring on his league debut for City when his free-kick was saved by Petr Cech, who denied Aymeric Laporte from the follow-up.
It was always going to be a tough first game for Unai Emery at Arsenal and they had few clear-cut chances - with Pierre-Emerick Aubameyang and substitute Alexandre Lacazette shooting wide from outside the box.
City were brilliant in parts - and controlled in others - and killed off the game when Benjamin Mendy, who assisted both goals, pulled the ball back for Bernardo Silva to blast in a second.
"We have a lot of players with a lack of condition but we are more than two seasons together and know what to do," Guardiola told BBC Sport. "We made a good performance in general and day by day we will get better and better.
"I am privileged to be manager of Manchester City. They have given me a fantastic squad. I cannot complain for one minute."
- Defeat in Emery's opener is a reality check for Arsenal - Keown
- Relive the game and read more reaction
- How you rated the players
City are the team to beat again
Pep Guardiola's City, who looked good in the 2-0 Community Shield win over Chelsea, were in fine form again. They only signed one first-team player - Mahrez in a £60m record deal - in the summer, and he went straight into their Premier League line-up.
Sterling, who was selected on the left wing over Leroy Sane, opened the scoring when he received a pass from Mendy, making his first Premier League start since September.
The England winger received the ball on the left corner of the box, beat Hector Bellerin and Matteo Guendouzi and then rifled a 20-yard shot past Cech, who must have been unsighted as he barely moved.
It was his 50th Premier League goal and a good start to the season after being harshly criticised during England's World Cup semi-final run.
"I couldn't wait for my holidays to finish," he told BBC Sport. "I needed to get back and I'm really happy I could be involved today. I wanted to play and it's great that we got three points."
By that stage Bernardo and Sterling had already had shots saved by Cech at his near post.
City kept pushing for a second goal that their performance deserved and went close when Arsenal's keeper denied Mahrez and Laporte.
Mahrez curled another shot just wide late in the first half. The Algerian put in a good performance on the right, and but was replaced by Kevin de Bruyne on the hour mark.
Record goalscorer Sergio Aguero should have had his 202nd City goal when he was played in one-on-one from the halfway line but he shot right at Cech - with De Bruyne free in the centre.
Bernardo finally sealed the points when he finished from Mendy's cutback.
City keeper Ederson played a few nervy passes late on - although Arsenal could not capitalise - and De Bruyne almost added a third with the last kick but Cech tipped his shot over.
"Every season is a major season and this game was complicated but we played at a high level. We created a lot of chances and our performance was good. We keep going," said Guardiola.
"We are satisfied for many, many reasons.
"At 1-0 we found a goal maybe we didn't deserve but in the first half we deserved to score two or three more."
How did new-look Arsenal perform?
It would be unfair to judge Arsenal - or Emery, who replaced legendary manager Wenger this summer - based on a performance against the country's outstanding team. The Spaniard failed to beat Guardiola in their first 10 meetings in La Liga and Europe and was never likely to end that run at the Emirates.
Arsenal started off brightly for the first five minutes and ended the first half strongly, with Aubameyang firing wide from 20 yards and Henrikh Mkhitaryan shooting into the side netting.
Two players made debuts from the start - experienced Greek centre-back Sokratis Papastathopoulos, a signing from Borussia Dortmund, and teenage holding midfielder Guendouzi, who was playing in France's second division with Lorient last season.
Guendouzi showed some good moments with tackles and passes although was beaten for Sterling's opener and allowed Aguero in for the one-on-one chance he should have finished.
He is likely to have a big role under Emery this season and when Lucas Torreira came on for his second-half debut, it was fellow defensive midfielder Granit Xhaka and not Guendouzi replaced.
"It's his first match here in the Premier League. He has personality and quality and if he is on the pitch he is improving very quickly," Emery told BBC Match of the Day.
Cech started in goal, instead of £19m summer signing Bernd Leno and justified his place with good stops from Bernardo, Sterling, Aguero and De Bruyne and especially the double save to deny Mahrez and Laporte.
With Nacho Monreal and Sead Kolasinac injured, Emery had suggested he could play forward Danny Welbeck at left-back - but Ainsley Maitland-Niles, usually a midfielder, got the nod instead.
The 20-year-old was given a torrid time by Mahrez and especially Kyle Walker, and ended up going off after 35 minutes when he hurt himself while stopping another Walker run.
Veteran Swiss right-back Stephan Lichsteiner came on for his debut on the left side in his place.
There were clear signs that Arsenal - who played a 4-2-3-1 - need more time to get used to the new system or gel with the fresh faces - with Ramsey - who only completed seven passes - Aubameyang and Ozil all playing the ball into empty space in the second half.
When City goalkeeper Ederson gifted Arsenal a late chance, Ozil mis-controlled the ball back to the goalkeeper.
"The result was 2-0 but I think on the pitch over the 90 minutes we were getting better," Emery said.
"The first half we didn't play like we wanted. We spoke at half-time about taking more responsibility for the second half, to do a little more. We wanted to build with the ball and break their lines. I think in the second half we played more like we want."
The former Sevilla and Paris St-Germain boss enjoyed the Emirates atmosphere. "We wanted to start here with our supporters. We wanted to show our performance but it is clear against Manchester City we could not give them this win. But I think here we are going to feel very well."
Man of the match - Raheem Sterling (Manchester City)
'We could have got something' - what they said
Arsenal keeper Petr Cech speaking to BBC Sport: "We feel that we could have got something from the game. In the second half, we forced them to make mistakes and we had some opportunities. Unfortunately, we lacked invention to find the killer pass.
"When you play against a team of City's quality and confidence it is always going to be difficult. Inevitably, you can make a few mistakes.
"It was a shame we couldn't finish off our counter attacks and overall we're disappointed with the defeat."
BBC Radio 5 live pundit Chris Sutton: "Let's not judge Arsenal on this performance against the best team in the land. I think they have shown grit, resolve and desire but I have been disappointed with them in the final third.
"City have laid down their marker on the Premier League with this performance. People could dismiss it as same old Arsenal which would be unfair in Unai Emery's first game. You have to say it though, they were outclassed in every department today."
Arsenal's opening-day woes - match stats
- Arsenal have just two victories in their last nine opening weekend Premier League games, drawing three and losing three.
- City are unbeaten in their last 10 opening Premier League fixtures (W9 D1), winning the last eight in a row.
- Emery is the first of Arsenal's last six managers (including caretakers) to lose his first league game in charge of the club, since Steve Burtenshaw lost 1-0 against Tottenham in March 1986.
- Guardiola remains unbeaten against Emery in all competitions, winning seven and drawing four of the 11 meetings.
- Guendouzi is the 27th French player to play for Arsenal in the Premier League - a joint record high with Newcastle.
- Lichtsteiner is the oldest outfield player to make his Premier League debut for Arsenal, at 34 years and 208 days.
- Sterling has now scored 50 Premier League goals, with his opener against Arsenal only his third from outside the box.
- Sterling has been directly involved in 12 goals in his last 12 Premier League appearances, scoring five and assisting seven.
- Mendy registered two assists in a game in Europe's big five leagues for only the second time ever (also for Monaco v Nice in February 2017) and for the first time ever away from home.
- Bernardo has scored five goals in his last seven Premier League starts for Manchester City after failing to score in his first nine.
Arsenal manager Unai Emery has got a really tough start - he follows this game up with a trip to Chelsea next Saturday (17:30 BST). City host Huddersfield on Sunday (13:30 BST).
- 5PapastathopoulosBooked at 27mins
- 15Maitland-NilesSubstituted forLichtsteinerat 35'minutes
- 34XhakaBooked at 52minsSubstituted forTorreiraat 70'minutes
- 8RamseySubstituted forLacazetteat 54'minutes
- 26MahrezSubstituted forDe Bruyneat 60'minutesBooked at 73mins
- 20Bernardo Silva
- 7SterlingBooked at 4minsSubstituted forSanéat 87'minutes
- 10AgüeroSubstituted forGabriel Jesusat 79'minutes
- 17De Bruyne
- 33Gabriel Jesus
- Michael Oliver
- Shots on Target
Second Half ends, Arsenal 0, Manchester City 2.
Corner, Manchester City. Conceded by Petr Cech.
Attempt saved. Kevin De Bruyne (Manchester City) right footed shot from outside the box is saved in the top left corner. Assisted by Leroy Sané.
Attempt missed. Alexandre Lacazette (Arsenal) right footed shot from the centre of the box is too high. Assisted by Henrikh Mkhitaryan.
Ilkay Gündogan (Manchester City) wins a free kick in the defensive half.
Foul by Stephan Lichtsteiner (Arsenal).
Leroy Sané (Manchester City) wins a free kick in the defensive half.
Foul by Héctor Bellerín (Arsenal).
Attempt blocked. Henrikh Mkhitaryan (Arsenal) right footed shot from the centre of the box is blocked. Assisted by Mesut Özil.
Attempt missed. Leroy Sané (Manchester City) right footed shot from outside the box is close, but misses to the left. Assisted by Kevin De Bruyne.
Substitution, Manchester City. Leroy Sané replaces Raheem Sterling.
Offside, Arsenal. Pierre-Emerick Aubameyang tries a through ball, but Mesut Özil is caught offside.
Attempt saved. Benjamin Mendy (Manchester City) left footed shot from the left side of the box is saved in the top centre of the goal.
Fernandinho (Manchester City) wins a free kick in the attacking half.
Foul by Alexandre Lacazette (Arsenal).
Gabriel Jesus (Manchester City) wins a free kick on the right wing.
Foul by Sokratis (Arsenal).
Substitution, Manchester City. Gabriel Jesus replaces Sergio Agüero.
Offside, Arsenal. Lucas Torreira tries a through ball, but Pierre-Emerick Aubameyang is caught offside.