After a promising pre-season campaign, Arsenal were comprehensively defeated by Premier League champions Manchester City on the opening weekend.Unai Emery's reign got off to the worst possible start as Pep Guardiola's outfit taught them a lesson at the Emirates Stadium, with goals from Raheem Sterling and Bernardo Silva giving City their first three points of the campaign.It's been all change at the North London outfit this season, with Emery replacing Arsene Wenger after a legendary 22-year reign.A new era has seen new signings, with Sokratis Papastathopoulos and Stephan Lichtsteiner arriving from Borussia Dortmund and Juventus respectively to bolster a defence that has been troublesome for years.In the middle of the park, Emery recruited Sampdoria's Lucas Torreira, the Uruguayan midfielder joining the Gunners for around £26 million, and in also came young prospect Matteo Guendouzi from Lorient in France.But arguably the most exciting addition came in the form of a new goalkeeper, as German international Bernd Leno joined from Bayer Leverkusen.Supporters saw Leno as the replacement for Petr Cech, who started to make more mistakes than usual last season, and was confirmed by Squawka as the most error-prone stopper in the Premier League for the 2017/18 season.So it was a surprise for fans to see Cech in the starting line-up for the City game last Sunday, and whilst making a few good saves to stop the scoreline from increasing any further, this was overshadowed by an embarrassing moment where Cech almost kicked the ball into his own goal under no pressure whatsoever.Calls for Leno to be brought in for the visit to Stamford Bridge to take on Maurizio Sarri's Chelsea seem to have been ignored by Emery though, as he's confirmed that Cech will retain his place between the sticks against his former club."I am very happy with his [Cech's] performance," stated Emery."Also I think he has experience and he has quality, he has the capacity like a first goalkeeper with us. Also with Bernd Leno [it's the same].

"They are two goalkeepers who are important for us. They have different qualities, but for us, in the way we want to play, they can [both] play.

"For Saturday, the decision for me is easy, because we'll continue to start the match with Petr Cech.

"I believe in him. But if we start with Bernd, I believe in him also."

Emery may be confident in Cech to produce the goods at his former stomping ground, but Arsenal fans don't share the same optimism.