The Chelsea player, however, was not completely confident of being ready for the first leg of the play-off.
"If the game was today I would not be able to play," Cech, who broke his nose against Blackburn Rovers in a Premier League game on Saturday, told a news conference on Wednesday.
"The mask will protect me from further injury but if I will be 100 percent I do not know. And in the play-offs you have to give 100 percent."
Czech coach Michal Bilek, already without suspended midfielder Tomas Hubschman, said of Cech: "I hope he will be ready; his presence on the pitch is very important for us because he is one of the best goalkeepers in the world."
If Cech cannot play, Bilek will turn to Hamburg SV's Jaroslav Drobny who started in the country's 2-2 draw with Scotland in qualifying.
The addition of Boskovic, who replaces Olympiakos's Petar Grbic, is the only change to the squad for the game in which Montenegro will be looking to slow down the Czech Republic's Arsenal playmaker Tomas Rosicky.
"We analysed them and noticed that Rosicky is a real leader in midfield," Brnovic said.
"If we neutralise him we have more chance. Generally speaking, the Czech team are very well organised, getting players behind the ball."
Central defender Miodrag Dzudovic said the team would have to repeat those performances if they were to eliminate the Czech Republic and reach next year's finals in Poland and Ukraine.
"We are looking at two very difficult games and unless the entire team plays to the best of our abilities, we have a very slim chance of beating the Czechs," he said.
"We have a realistic chance if we stick to our 'all for one and one for all' mentality.
"Of course it would be great to keep a clean sheet in the first leg in Prague but that doesn't mean we should sit back and defend, because our strikers Mirko Vucinic and Stevan Jovetic are the team's two outstanding players," he said.
