Pierre-Emerick Aubameyang and Alex Lacazette found the net as we grafted our way to victory over a resolute Cardiff side.
Aubameyang’s 18th goal of the season came from the penalty spot, but he owed a debt of gratitude to Alex Iwobi, whose perfect pass sent Sead Kolasinac into the box. The Bosnian went down under a mistimed challenge from Bruno Ecuele Manga.
Aubameyang did the rest - to the relief of an increasingly anxious home crowd.
Lacazette gave us a two-goal cushion with a powerful low finish after a barnstorming run into the box. And we held on to the points despite a stoppage-time strike from Nathaniel Mendez-Liang.
Mesut Ozil returned to captain our side and was influential in the opening stages, although it was Lacazette who almost opened the scoring after Matteo Guendouzi carved open the Cardiff defence.
The tone appeared to be set, but Cardiff had other ideas.
Bobby Reid went close twice in quick succession - with a shot marginally wide and a header just over - and the visitors demanded a penalty when Kolasinac muscled Oumar Niasse off the ball.
Cardiff didn’t get what they wanted but we looked vulnerable, despite having our own penalty shout turned down moments later when Lacazette was tripped.
We needed a spark - and Iwobi provided it.
The Nigeria international replaced Mo Elneny at the break and it was his vision that picked out Kolasinac’s run into the box, which in turn provoked a foul from Manga.
This time Mike Dean pointed to the spot and Aubameyang rolled in the penalty.
Iwobi went close to a second with a shot from a narrow angle after a driving run, but Lacazette made sure of the points with his 11th goal of the season.
A MOMENT OF REFLECTION
Everyone at Emirates Stadium paid tribute to the Argentine striker Emiliano Sala and pilot David Ibbotson ahead of this game.
The plane carrying them from France to Wales disappeared on Monday, and a three-day search of the English Channel was called off on Thursday.
Cardiff City's staff and fans wore yellow daffodils, and wreaths of flowers were laid in the centre circle ahead of kick-off to honour the missing men.
THREE THINGS WE NOTICED
HOW IT HAPPENED
WHAT IT MEANS
This result keeps us in fifth place, level on points with fourth-placed Chelsea having played a game more.
Unai Emery made seven changes for this game - with all seven substitutes against Manchester United getting a chance in the starting line-up.
That meant returns for Ozil, Bernd Leno, Nacho Monreal, Elneny, Shkodran Mustafi, Guendouzi and Stephan Lichtsteiner - with Ozil taking the captain’s armband.
We lined up with a back four and a midfield diamond that had Elneny at the base and Ozil at the tip, behind a front two of Lacazette and Aubameyang.
Our Premier League campaign continues on Sunday with a tough trip north to face the champions, Manchester City.
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