Coach Fernando Santos insists he has paid no attention to the Czech Republic's heavy defeat to Russia during Greece's preparations for their Group A meeting in Wroclaw.
The Czechs sit bottom of the group after being thoroughly outplayed by an impressive Russia side on Friday. Greece, meanwhile, played out a 1-1 draw with co-hosts Poland and know that victory would see them dump the Czechs out of the tournament.
But Santos knows Michal Bilek's side still pose a major threat, and said: "It changes nothing that they lost against Russia. They're compact, and have a lot of pace. In the game against Russia, the Czechs had the upper hand in the opening 20-25 minutes. I think they showed their qualities, despite their 4-1 loss."
Santos faces a selection headache when it comes to picking his starting XI at the Municipal Stadium.
Defender Sokratis Papastathopoulos is suspended after his harsh first-half sending-off against Poland in Warsaw, while Avraam Papadopoulos suffered a torn cruciate ligament.
Kyriakos Papadopoulos is set to come into defence but midfielder Giorgos Fotakis is another absentee with a thigh injury.
Bilek, meanwhile, is set to make changes to his starting line-up, with Michal Kadlec set to revert to centre-half after struggling at left-back against the Russians and David Limbersky likely to start. Striker Milan Baros might also miss out.
And goalkeeper Petr Cech has warned the Greeks they will face a fired-up opponent.
The Chelsea player told uefa.com: "I think the anger (of defeat) has changed into determination. Determination to fix the bad start we had in the tournament.
"We felt the disappointment immediately afterwards, for sure. We did not succeed in any way in that first match, but we know we have another 180 minutes to play to allow us to qualify for the quarter-finals. So we're determined to do just that."