The former Hannover goalkeeper signed for the Foxes last week.
"Anyone who knows me knows that, of course I want to play as much as possible. Kasper Schmeichel played well last season, you have to recognize that. But in conversations with those responsible I was assured that it is an open duel," Zieler told BILD.
"I am ready for the challenge."
He continued: "There have been some inquiries from the Bundesliga, also teams from abroad. Then came the offer from Leicester. Since then I have not thought twice."