Edu believes Arsenal have added players with winning mentalities this summer.
The Gunners technical director has signed Gabriel Jesus, Oleksandr Zinchenko, Fabio Vieira and Marquinhos this summer.
"I think we've added some more players with that kind of character," Edu told football.london.
"Talk to Gabriel, talk to Zinchenko, talk to Fabio. [Points to head] Here is the win. Ah, Champions League, ok — I accepted that, because I want to be realistic. But here [head], I want to win. A club like Arsenal, at our size, is not building to be fighting for fourth place. I'm sorry.
"We have to be realistic — there's City, Liverpool etc — that's fine, I accept that. But also, you can not accept that. Here, when you join this club, when you see our size, we cannot accept it.
"That's why I was really really hurt when I arrived. I said, 'That's not the mentality of this football club. What's happening? Everybody's comfortable, everybody's ok, ok, ok…' F*** you, "ok"! "Ok"?! No, I don't want to lose games! We have to be there again."