Speaking to the media about Szczesny, Pena said: "As a person, he is a phenomenon.
"We know that he is a goalkeeper with a lot of experience, who has played for many European teams at the Champions League level and he is going to help us. In terms of competitiveness, we train at 100 per cent so that the manager gives us opportunities and he decides. Today it is my turn and we will see what happens in the future, we never know.
"He came to compete, to help, to add another goalkeeper and they saw the opportunity to sign him and with him, on a personal level, I'm doing very well and very happy."