Leno said: “Petr had a big career with many, many trophies and he's still a big goalkeeper and a big personality.
"But I have to look at myself and play my game, work every day, very hard, to be the first choice of the coach.
“I will learn a lot working with him every day. He has big experience and played many games. I have a lot of experience too, but he has much more, so I can learn from him.
“He is a goalkeeper I admired when I was growing up. I can remember my first game in the Champions League, when I was 19, was against Petr. After the game, he said it was a good game for me.
“It was seven years ago and now we are together at Arsenal, it's crazy."
Asked if manager Unai Emery had told him or Cech who is going to be No.1, Leno added: “No. I don't know.
“I do my best, I work every day very hard and at the end the coach has to decide."