Czech Republic captain Tomas Rosicky left Poland for Prague on Sunday for treatment on the Achilles tendon injury that ruled him out of Saturday's 1-0 Euro 2012 Group A win against Poland, Czech media said Monday.
The Czech Republic won Group A and will face Portugal in the quarter-final in Warsaw on Thursday.
"We wanted to carry out procedures we are not able to do here. We won't say which procedures," the website of the DNES broadsheet quoted chief team doctor Petr Krejci as saying.
The 31-year-old Arsenal midfielder - who suffered a calf injury in his club's final Premier League game of the season that nearly cost him his place at the tournament - is due to return to the southwestern Polish city of Wroclaw, where the Czechs have set up camp, on Tuesday.
Rosicky limped off at half-time in the game against Greece on June 12, which the Czechs won 2-1, and was replaced by Viktoria Plzen midfielder Daniel Kolar for the rest of the match and in the game against Poland.
Rosicky said after the Poland game he was unlikely to play in the quarter-finals.
"There is just a small chance I will play in the quarter-finals but it's really not big," said Rosicky.