Alex Lacazette smashed in a late winner as we eventually shook off a spirited Cardiff side in Wales.
The France striker found the roof of the net from a narrow angle, set up a goal for Pierre-Emerick Aubameyang and even hit the post - not a bad return on his return to the starting line-up.
Harry Arter should have given Cardiff an early lead when he blazed over after intercepting a pass from Petr Cech that was meant for Matteo Guendouzi.
Instead it was Shkodran Mustafi who opened the scoring. The centre back made a darting run to the near post to meet Granit Xhaka’s corner and powered a header into the top corner.
Goalkeeper Neil Etheridge denied Aaron Ramsey a goal on his return to his former club - after more good work from Lacazette.
Cardiff had their fair share of chances too and might have levelled when Danny Ward missed Bobby Reid’s cross by a matter of inches.
Victor Camerasa did find an equaliser in first-half stoppage time, getting the better of Monreal to rifle a shot into the roof into the net.
Aubameyang restored our lead in an equally entertaining second half, latching onto Lacazette’s neat flick to curl a shot beyond the dive of Etheridge from just outside the box.
But once again we couldn’t shake off a spirited Cardiff side. This time Sean Morrison climbed well to head the ball across goal and Ward guided a header in off the post.
Frustration was setting in, but Lacazette had the last word - in emphatic fashion.
HOW IT HAPPENED
FOUR THINGS WE NOTICED
Unai Emery made two changes from the team that best West Ham United.
Alex Iwobi was sidelined by illness and Henrikh Mkhitaryan dropped down to the substitutes bench. In came Mesut Ozil and Alex Lacazette.
Aaron Ramsey returned to Cardiff to face his former club - 10 years after leaving them for us.
Laurent Koscielny, Sead Kolasinac, Ainsley Maitland-Niles and Carl Jenkinson are still recovering from injuries.
We head into an international break now but you can still see an Arsenal game - the legends face Real Madrid at Emirates Stadium on September 8 and tickets are still available.
The first team will be back on the road when the Premier League resumes. We’re at Newcastle United on September 15.
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