Cech himself admitted that he was being asked to perform differently from the majority of his career by sometimes playing nearly as a spare outfielder and had his efforts highlighted on social media by new signing Bernd Leno's former club Bayer Leverkusen.
The Spaniard brought Bernd Leno in from Bayer Leverkusen this summer, but the German warmed the bench during Arsenal's Premier League opener against City as Cech manned the posts.
Speaking to reporters ahead of Arsenal clash with Chelsea on Saturday, Emery urged the former Real Madrid player to show more commitment to defending. Also, with Bernd Leno - they are two goalkeepers who are important for us.
"We played two or three weeks ago against Chelsea [in pre-season], but with different players on the pitch, to Saturday - Hazard, Kante, Giroud, Kovacic".
"We are going to play away but we need to keep our personality, keep our mentality", he said.
Petr Cech was left unamused after a video appeared on Twitter mocking an attempted pass that nearly resulted in an own goal in the match between Arsenal and Manchester City, getting over 7,500 likes since it was posted on Sunday.
"It was a little bit of a mish-mash of a performance, the kind of thing I have seen before where a manager is new to the Premier League and does not really grasp what it is all about".
"We are training for each situation". 'He has experience, quality, the capacity. We need to work hard and together.
With several leagues around Europe still able to wheel and deal, as well as clubs in the Football League having the opportunity to sign players on loan until the end of the month, a number of Arsenal players could be on the move.
The first game gives us more information about things to improve and also things to continue doing. I want in each moment to know what is our best action to do in the match.
"For Saturday, the decision for me is easy".
"Hi Petr. It seems our joke about wanting to see Leno, our former player, in action has been taken a bit more harshly/personally than intended".
"We didn't lose [against Manchester City] because of our personality, our idea, our style", he said.