Poland will play the Netherlands at the National Stadium in Warsaw on Thursday before taking on Wales in Cardiff on Sunday.
Manager Czesław Michniewicz last week released a list of 30 players called up for the two games.
The lineup includes star striker Robert Lewandowski, FIFA's world player of the year for 2020 and 2021, and other regulars such as Napoli midfielder Piotr Zieliński and Juventus goalkeeper Wojciech Szczęsny.
Fresh faces include Ludogorets Razgrad midfielder Jakub Piotrowski and Lech Poznań winger Michał Skóraś.
Lewandowski: 'I feel good in Barcelona'
During a news conference in Warsaw on Monday, Lewandowski, the Poland captain who plays for Spanish giants Barcelona, said: "A lot has changed in my life in recent months. There are many reasons to be satisfied. I'm always happy to come to play for the national team."
Referring to his recent move from German champions Bayern Munich, he added: "After so many years of playing in one place, a change is something new and welcome. I feel good in Barcelona. I am where I wanted to be. And this explains the smile on my face and the form that I have enjoyed in recent matches."
Lewandowski has scored eight goals in six appearances in the Spanish top flight this season.
The 34-year-old was in July officially unveiled as a player for Barcelona after eight years with Bayern.
Countdown to Qatar
After four rounds of Nations League fixtures, Poland are third in their Group A4, with four points, three less than Belgium and six less than the Netherlands.
The Nations League is the European football governing body UEFA’s newest national-team competition that is now in its third edition.
The competition is designed to enable teams to play against those that are similarly ranked and may also offer an alternative path for teams to qualify for the 2024 European championships.
Portugal won the first edition of the Nations League in 2019, while France won the 2020/2021 UEFA Nations League after beating Spain 2-1 in the final in Milan last October.
Meanwhile, in late March, Poland secured a berth in this year's World Cup finals in Qatar after defeating Sweden 2-0 in a playoff at home.
The Poles have been drawn to play Argentina, Mexico and Saudi Arabia in the group stage of the tournament, which will be held in Qatar from November 20 to December 18.
Before heading for the World Cup, Poland are scheduled to play a friendly against Chile at the National Stadium in Warsaw on November 16.
Source: PAP, polskieradio.pl