Spoil the party
A win in Saint-Etienne will secure Croatia's place in the last 16 in the competition, but Pavel Vrba's side will be looking to spoil the party.
Despite their 1-0 defeat to Spain in their opening game, there was many positives to take.
They had some excellent opportunities, but it was Gerard Pique's later header that proved their downfall, and Vrba said that there will be changes ahead of the game.
Vrba told uefa.com that Croatia are a "little like Spain" as most of their team "play abroad" and are "very strong opponents" and admitted that their opponent is one of the "most difficult" in the group.
He continued by saying that by having Theodor Gebre Selassie in defence in Spain meant that they had "think a lot" about their defensive line-up, and said that they will "think more about forwards" against Croatia.
Sealing the passage
Croatia were considered one of the dark horses heading into this tournament, and lived up to the expectations in their curtain raiser against Turkey.
Their 1-0 win was won in spectacular style, as Luka Modric fired home a spectacular first-half volley, but Cacic believes that it will be another tough test for his side.
Cacic said that the Czech Republic's "biggest quality" is that they are a "real team" with Tomas Rosicky been their "most important player" and all their opponents need to "think about him" as well as themselves.
He continued saying that their opponents "need points" but expects his players to have "same approach" as their first game and are coming into this game in "good spirits" and his side "need to go for a victory" in "every match."
It is set to be an emotional game for Croatia captain, Darjo Srna, who traveled back to his home nation for the funeral of his father but is expected to start.
One player who will be included is Modric, and Cacic said that he is vital to his team's potential progression.
He told the press conference that their whole game "revolves around Modric" and have to "keep him fresh" but is in "good physical and mental shape" and will "definitely start."
Czech Republic: Čech; Kadeřábek, Sivok, Hubník, Gebre Selassie; Darida, Plašil; Dočkal, Rosický, Krejčí; Necid.
Croatia: Subašić; Srna, Ćorluka, Vida, Strinić; Badelj, Modrić; Brozović, Rakitić, Perišić; Mandžukić.
Czech Republic will take on Croatia at the Stade Geoffroy-Guichard, Saint-Etienne, on Friday, June 18 with kick-off at 5pm BST.