Sadilek's absence could open the door for Lukas Provod and Antonin Barak to operate in the middle of the midfield alongside captain Tomas Soucek at the tournament, with the national side's Group F opener coming against Portugal on Tuesday night.
Czech Republic are expected to line up in a 3-5-2 formation for this match, with David Jurasek set to feature as the left-sided wing-back, with Vladimir Coufal on the opposite side.
Head coach Ivan Hasek has a big decision when it comes to the final third of the field, as he must choose a player to operate alongside Patrik Schick.
Jan Kutcha could just get the nod ahead of Adam Hlozek, with the former finding the back of the net on three occasions for his national side.
Schick is the leading goalscorer in the squad with 19 and is an absolute certainty to be in the XI, with the forward bidding to add to the five goals that he has managed at the European Championships.
Tomas Holes, Robin Hranac and Ladislav Krejci are likely to feature as the back three for the Czech Republic, while Slavia Prague's Jindrich Stanek is the country's number one goalkeeper.
Czech Republic possible starting lineup: Stanek; Holes, Hranac, Krejci; Coufal, Soucek, Provod, Barak, Jurasek; Kuchta, Schick
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