Poland coach Michal Probierz said his team had not said their "last word" at Euro 2024 despite an opening defeat by the Netherlands on Sunday, with striker Robert Lewandowski poised to return from injury.
The Barcelona forward did not feature as the Dutch emerged 2-1 winners in the Group D clash in Hamburg, but is hoping to face Austria on Friday.
Poland gave as good as they got in the second half against the Netherlands but Wout Weghorst struck a late winner for the Oranje.
"Robert Lewandowski is coming back to strength and he will hopefully play against Austria – he's a very important player for us," Probierz told reporters.
"We are not giving up. We'll give everything to fight and qualify.
"We still have something to prove and we'll be stronger."
Adam Buksa started in Lewandowski's position and headed Poland ahead from a corner after 16 minutes, but Cody Gakpo soon levelled for the Netherlands before Weghorst's decider.
"In football you have phases where you break the opponent or you get broken," said Probierz.
"We missed that smartness in the last moment of the match."
Austria face France on Monday and have a day's less rest before the teams meet in the German capital, although Probierz said it did not matter.
"At the professional level I don't think one day's difference matters," he said.
"We've not said our last word, we'll try to play a wiser match against Austria. In a tournament you need to play wise football."
Lewandowski's return could give Poland an edge up front which they missed at times and boost the team's confidence, something the coach has already tried to do.
"We have shown that we can play football very well, we had our own chances and I told the players to keep their heads up, we can play against any opponent," Probierz added.