The announcement by the chief of the national governing body for the sport came after Brzęczek unexpectedly lost his job as Poland boss on Monday.
Sousa, 50, is a Portuguese soccer manager and a former professional player who played as a defensive midfielder. His credits as a coach include Leicester City, Italian side Fiorentina and France's Girondins Bordeaux.
The head of the Polish Football Association (PZPN), Zbigniew Boniek, told a virtual press conference on Thursday afternoon that the national team needed a new manager to put an end to "a sense of malaise" among players and ensure more quality ahead of the upcoming European championships and qualifiers for the 2022 World Cup in Qatar.
Zbigniew Boniek, head of the Polish Football Association (PZPN), is seen on a screen during a virtual news conference on Thursday. Photo: PAP/Piotr Nowak
"The upcoming matches, both World Cup qualifiers and the Euro tournament, require that the squad steps up its game," Boniek told reporters.
Boniek on Monday thanked Brzęczek for his work with the national team in a statement.
Brzęczek was fired even though he in May last year agreed a contract extension to manage the Polish national football squad until at least the end of 2021.
The extension was announced after last year’s European championships were postponed until 2021.
The Polish team in 2019 celebrated advancing to the European tournament for the fourth time after a successful qualifying campaign.
Brzęczek, a former Poland captain, took over as Poland manager to replace Adam Nawałka in the summer of 2018 after the national squad's early World Cup exit disappointed fans.
Brzęczek, 49, had a professional career that spanned nearly 20 years and brought him 42 international caps as a midfielder with Poland.
He captained the national team when they won silver at the 1992 Summer Olympics. He later spent 12 years playing abroad from 1995 to 2007.
Prior to becoming Poland boss, he coached top-flight Polish side Wisła Płock.
Source: PAP, pzpn.pl
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