Shkodran Mustafi has branded criticism from Arsenal fans "irrational" and insists it does not get to him.
The Germany centre-back, who was up for sale in the summer but remained at the Emirates, is aware of the extent of negativity he receives online from his club's own supporters.
Manager Unai Emery said earlier this season that Mustafi would be as important a member of his squad as anyone else, but has not played a single minute in the Premier League, turning out only in the Europa League.
Speaking to German publication Der Spiegel during the international break, he said: "In the first two years after my move to Arsenal in 2016, things went very well for me. I saw myself as a performer.
"But shortly after Christmas 2018 there was a kink. I've made a few mistakes and they've created a mess that I've never experienced before.
"I had missed three weeks injured and then went into the [Liverpool] game without training with the team because the coach needed me. At half-time it was 4-1, I looked bad a few times and have injured myself again.
"Afterwards, I got a lot of negative comments from Arsenal fans on Instagram and Twitter, and articles were written in which I was harshly criticised. I'm self-critical enough to realise that I made those mistakes. I can also deal with tough criticism.
"But the criticism has become escalated and irrational. I have become a target. At some point, people even blamed me for a defeat I had not played in at all.
"There were days when I really doubted something about myself. But at some point I realised that I am mentally strong. Something my wife said helped me a lot. Since then I can handle it better."