We fell to defeat at Emirates Stadium, as three first half goals from Manchester City secured the visitors all three points.
Here's three things we noticed from the defeat to the champions:
Kevin De Bruyne's opening goal came after just one minute 29 seconds – the second quickest goal we have ever conceded at Emirates Stadium (Fulham's David Healy netted inside a minute back in August 2007).
It was the sixth Premier League game in a row that we have conceded the first goal of the game – our longest such run in the competition's history – so it was always going to be difficult from then on. But it could have been so different, as the first chance of the game fell to us.
Gabriel Martinelli burst through and forced a good save from Ederson after just 33 seconds - but that was as good as it got for us in truth. It was our only shot on target all afternoon, the lowest tally we have mustered at home for three years.
City showed ruthlessness to score with each of their first three shots on target, it would have been four as well but for a magnificent, full-strength save from Bernd Leno to deny De Bruyne his hat-trick late in the first half.
BUKAYO AT THE BACK
Kieran Tierney has been ruled out for up to three months with a shoulder injury, so Sead Kolasinac was one of two players brought into the team that beat West Ham on Monday. However, when the Bosnian was also forced off injured late in the first half, Freddie Ljungberg was running out of options in the left full-back position.
He turned to Bukayo Saka, who impressed at left wing back in midweek away to Standard Liege. The speedy youngster has played at full back before - for both Arsenal's and England youth sides – and he gave a solid showing up against Raheem Sterling. In fact it remained goalless while Bukayo was on the pitch, as he wasn't introduced until after De Bruyne's second goal. City took advantage of us being down to 10 men following Kolasinac's withdrawal, Saka waiting patiently to come on on the sidelines, only for the ball not to go out of play until City scored.
PREMIER LEAGUE DEBUTANT
Emile Smith Rowe had already played 10 times for the first team after progressing from our academy, but today's appearance was his first taste of the Premier League.
Still only 19, he was one of three Gunners teenagers on the pitch when he was introduced on the hour mark, and he looked neat and tidy on the ball when he received it in the number 10 position, just behind the forwards, completing 12 of his 13 passes – eight of which were in the opposition half.
The England youth international has been frustrated with injuries in recent times, so this will feel like an important milestone for him. And he knows he won't come up against opposition quite as strong as this too often, however long his Premier League career turns out to be.
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