Attacking unit
Aubameyang looked isolated as a sole striker. The playmakers struggled to feed him with balls as a result of City's tight defensive play, but Aubameyang wasn't efficient against both sides. He missed a sitter against the Blues. However, when Lacazette came in, Aubameyang was shifted to the left wing, as Lacazette prefers to play as a striker. And Aubameyang looks better when he is given a wider role as his pace helps him beat defenders.Aubameyang and Lacazette forge a strong attacking duo and Emery must use them both in the upcoming game.
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Mkhitaryan or Ramsey should be given the central role, and Ozil plays beautiful football as a right winger, though he mostly moves into the centre with Bellerin taking the right wing.
Conclusion
Arsenal has always suffered in the defending department, but that doesn't seem to be a problem this year. Their defence looks sorted. City not scoring in a game is impossible, so this loss against City is just a reality check for Emery and co. But they should have done a finer job in defending against Chelsea. The Arsenal team is clear about the level of football they have to produce for a top three finish, and Emery is capable of doing that with his squad. Not conceding against the top 6 is pretty difficult, but the scoreline would have been probably equal or in favour of Arsenal if their attackers did their job well in both the matches.
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With two back-to-back defeats, they have already lost six points. The Gunners have to start winning, with the game against West Ham coming up next weekend