Czech Republic captain Tomas Rosicky's latest injury concern threatens to derail a team that finally came up with a potent attacking display against Greece at Euro 2012.
Rosicky went to hospital for a scan on his Achilles on Wednesday along with keeper Petr Cech who has a sore shoulder. They have been given a 75 percent chance of being fit.
Coach Michal Bilek has therefore been left to sweat over whether they can shake off their injury problems for the Czechs final Group A match against co-hosts Poland on Saturday.
Rosicky was instrumental in the quickfire start that saw the Czechs take a two-goal lead in six minutes on Tuesday as he helped open up a makeshift defence with incisive passes.
But the playmaker had to come off at half-time and was sorely missed in a turgid second half when the Czechs creativity all but disappeared leaving them to hang on for a 2-1 victory.
"We wanted to attack even more but it was difficult when Rosicky left," Bilek said. "He is our key player."
Russia's 1-1 draw with Poland kept them top of the group with four points ahead of the Czech Republic on three and Poland with two while Greece are bottom with just one point.
But the Czechs will be wary of a Polish side that showed it was possible to soak up Russia's early attacks and create their own chances, something Bilek's side spectacularly failed to do in their opening 4-1 loss to the group favourites.
If Rosicky, who missed the final two Euro warm-up games with a calf injury, does not play the Czechs will look to Daniel Kolar to take his place and direct their attacks.
Young midfielder Vladimir Darida, a last-minute addition to the squad due to Rosicky's injury worries, is another option.
The Czechs must also find a way to get striker Milan Baros firing on all cylinders. The Euro 2004 Golden Boot winner has scored just three times for the national team in the past two years but has failed to fashion any decent chances so far.
All three Czech goals so far have come from two midfielders playing in their first major tournament, making it vital that the experienced Rosicky can play against Poland.
"It is [always] a great loss to not have Tomas Rosicky on the pitch," said Vaclav Pilar, who has scored a goal in each game. "He is our key player."