Petr Cech admits he was left bitterly disappointed by the reaction of a number of Chelsea fans after his departure from the club.
The 33-year-old has received several death threats from Chelsea fans on social media following his £10m move to the Emirates.
He was labelled a "snake" and a "traitor" on Twitter from what the goalkeeper called "non-true Chelsea fans".
"The true fans have sent me messages that are pleasing and positive," Cech is quoted as saying by The Guardian.
"True fans will appreciate what I've done and the legacy I've left.
"There are some people who have left me negative messages, but they aren't true Chelsea fans.
"The last few days were really overwhelming.
"The welcome messages from my team-mates and Arsenal fans were absolutely unbelievable.
"Last season it was a great season [for Arsenal], but there was something missing, just a little last jump over the hurdle.
"I believe this team has the potential to challenge for trophies."