Cech signed a four-year contract at Emirates Stadium on Monday, immediately putting the futures of Szczesny, David Ospina and Emiliano Martinez into doubt.
Szczesny had already lost his place as first choice to Ospina last season, and Polish goalkeeping legend Jan Tomaszewski believes the 25-year-old should now look for a move elsewhere.
“Wojciech must be devastated,” Tomaszewski told Polish newspaper Przeglad Sportowy.
“In January I spoke to [Poland manager] Adam Nawalka and he said that Arsene Wenger had told him that if Szczesny worked hard in training he would play again soon.
“It turned out that he didn’t tell the truth. I’m sure that when Szczesny said that he was going to stay at Arsenal, he didn’t know that Cech was going to come because Wenger didn’t tell him about his plans. Szczesny should leave, because it will be waste of time for him, if he stays.
“This [Petr Cech transfer] is a big problem also for the Polish national team.
“For me Wojciech is still Poland’s number one, world class goalkeeper but after Cech’s transfer he has no chance to play at Arsenal and for Poland. It could be end of his career in the national team.”
According to reports, it could be Ospina rather than Szczesny that leaves Arsenal this summer, with Fenerbahce said to have enquired about the Colombian’s availability.