The Toffess dominated the first half, with Cech forced to make a number of decent stops to keep out the likes of Dominic Calvert-Lewin, Lucas Digne and Richarlison who looked sharp on his return from suspension.
Cech, 36, has captained Arsenal in all of their Premier League games since Emery took charge but has not been without his critics as he adapts to playing the ball out from the back.
He has kept summer signing Bernd Leno on the bench – except for Thursday’s Europa League win over Vorskla Poltava – and Emery is pleased with his goalkeeping options.
After the win, Emery said, “I am a little surprised because there have been a lot of questions over Cech,”
He continued by saying, “In pre-season and also in the first league matches with us, he’s played with good performances. Bernd Leno will also improve with us and learn about this competition here. Petr has big experience and big quality. He’s started the season very well and we think he’s giving us the performance we want. Today he showed us that he’s very good and continuing to work hard with this spirit every day.’
Lacazette opened the scoring with a well-taken strike, three minutes before Aubameyang’s tap-in secured the win, and three points for the Gunners.
And Cech got his first clean sheet of the season.