City's left-back missed nearly the entirety of last season through injury, and his overlapping will bring an extra dimension to City's attacking play.
Emery faced Pep Guardiola regularly when they were in charge of Valencia and Barcelona respectively.
"We have a lot of ambition to start (well) on Sunday against the last winners of the Premier League", Emery told a news conference.
City were almost ideal last time out, winning the league with a record number of points (100), goals (106) and points margin (19).
People say now we have to forget what we did last season.
Arsenal finished sixth last season as they completed their campaign in dismal fashion. That's the basic principle, ' he urged.
He'll be among the players Arsenal will have to keep a close eye on if they're to stand any chance of getting a result.
Maitland-Niles isn't a natural left-back, although was deployed there on various occasions last season, and his right-footedness might help if Guardiola deploys Riyad Mahrez on the right flank, as the Algerian is always attempting to drift inside onto his left.
Pep Guardiola claims simply winning matches, not more titles, is his main motivation as champions City begin their Premier League defence.
"The important thing is to be there and to be ourselves". The likes of Kevin de Bruyne and David Silva are not expected to be up to speed yet but City still looked a class apart without them when they beat Chelsea in the Community Shield last weekend.
Midfielders Kevin De Bruyne and Raheem Sterling are back in contention for City.
'Any bad moments in the World Cup, start again.
Having missed out on the Champions League, Arsenal will play in the Europa league but boy aren't they in safe hands! It hurts a lot.
'It is not comfortable but if you want to compete in four competitions we cannot compete with just two good central defenders. But Sunday, we need to show on the pitch our performance at a big level. They have to compete between each other and accept my rules, today don't play but tomorrow you are going to play and you have to be ready'. Are you telling me they didn't deserve to play?
Eventually, Stones might be deployed as a holding midfielder with City losing out to Chelsea in the race for Jorginho.
Guardiola has no doubt Arsenal, who are at the start of a new era under Unai Emery, can prove to be one of the challengers.
No club has retained the title since Manchester United in 2008-09. Maybe Liverpool, Arsenal, Tottenham and Chelsea can do their job better - but if we do our job, we will be there.