The major issue is at left-back, where Sead Kolasinac is definitely out and Nacho Monreal is considered doubtful, which may mean Ainsley Maitland-Niles starting.
The Gunners have bolstered their significantly in the off-season with the arrival Matteo Guendouzi, Bernd Leno, Stephan Lichtsteiner, Sokratis Papastathopoulos, Lucas Torreira. Even without key players the intensity and organisation of Guardiola's men could not be matched by Arsenal, just as it couldn't by Chelsea in last week's Community Shield. Playmaker David Silva could also feature after sitting out at Wembley and goalkeeper Ederson will return. But City, fresh from their record points total last season, started 2018-19 with an incredibly dominant victory at the Emirates with goals in either half from Raheem Sterling and Bernardo Silva.
Emery has also pored over film of Arsenal's woes last season and his pre-season transfer dealings suggest he has already identified the problems that Wenger struggled to resolve. City beat the Gunners - home and away - with the minimum of fuss last season.
Koscielny, now out with an ankle injury, captained the side in place of Per Mertesacker last season.
Emery was hired to replace Wenger following the Frenchman's exit at the end of a dismal campaign which saw Arsenal labour to a sixth place finish in the Premier League.
Where is the Arsenal vs Manchester City, Premier League fixture being played?
His manager might be thrilled about Welbeck's versatility but Arsenal fans are crossing every body part they have in the hope that they don't see their striker line up at full-back against the rampaging attack possessed by Pep Guardiola.
Arsenal's defensive signings will give their forward players more freedom and Aubameyang is one to exploit this and torment the opposition.
So let's take a look at the expected Arsenal lineup to face Manchester City today. His clinical nayure and proper positioning will make him a threat for City, and he indeed is the one player to watch out for when the two sides meet.