Kostas Fortounis is in Greece's Euro 2012 squad, but Alexandros Tziolis and Panagiotis Kone have missed out.
Kaiserlautern's Fortounis, 19, has only won two caps to date but has done enough to persuade coach Fernando Santos he is worth taking to Poland.
However, experienced defensive midfielder Tziolis has failed to make the cut due to a lack of match action for Monaco, whom he joined in February.
Santos said: "We know that Tziolis hasn't played enough this season. But that's why we take players along to the training camp, to check out their condition."
The other player omitted by the Portuguese coach is attacking midfielder Kone, who spent last season on loan at Bologna.
Greece's final friendly is against Armenia in Austria on Thursday.
They then kick off the tournament against co-hosts Poland in the Group A clash in Warsaw a week on Friday, before facing the Czech Republic and then Russia.
Squad: Kostas Chalkias (PAOK), Michalis Sifakis (Aris Thessaloniki), Alexandros Tzorvas (Palermo); Vassilis Torosidis (Olympiacos), Kyriakos Papadopoulos (Schalke), Sokratis Papastathopoulos (Werder Bremen), Avraam Papadopoulos (Olympiacos), Jose Holebas (Olympiacos), Giorgos Tzavellas (Monaco), Stelios Malezas (PAOK).
Midfielders: Kostas Katsouranis (Panathinaikos), Giorgos Karagounis (Panathinaikos), Giannis Maniatis (Olympiacos), Giorgos Fotakis (PAOK), Grigoris Makos (AEK Athens), Giannis Fetfatzidis (Olympiacos), Sotiris Ninis (Panathinaikos), Kostas Fortounis (Kaiserslautern); Dimitris Salpigidis (PAOK), Giorgos Samaras (Celtic), Fanis Gekas (Samsunspor), Nikos Liberopoulos (AEK Athens), Kostas Mitroglou (Atromitos).