Croatia coach Slaven Bilic said on Monday, on the eve of his squad's departure for Euro 2012, that their poor performance in a friendly against Norway last Saturday had not dampened his optimism.
"I expected more from the match against Norway, but there is no need to panic," Bilic told reporters in Zagreb.
"We did a great job (with the qualifying) ... so my optimism ahead of the European Championship has not been dampened."
The Croats - quarter-finalists at Euro 2008 - did not impress in the 1-1 draw with the Norwegians in Oslo and hardly suggested they would live up to Bilic's expectations of reaching the quarter-finals.
Croatia have been drawn in Group C with champions Spain, Italy, and the Republic of Ireland. But despite the tough draw Bilic repeatedly stressed that he believes his side can reach the quarter-finals.
The former Yugoslav republic play their first match at the championship, hosted jointly by Poland and Ukraine, against Ireland on Sunday.
Captain Darijo Srna echoed Bilic's view and said that Saturday's match did not reflect Croatia's real strength.
"We will show our character and our real face in the match against Ireland," said the 30-year-old.
Bilic did not want to comment on the outcome of the match between Italy and Spain.
"We are interested in Ireland only and I don't concern myself with the outcome of the other match," stressed the 43-year-old who is taking over Russian Premier league side Lokomotiv Moscow after the championship.
Meanwhile, Bilic suffered a serious blow also on Monday as veteran striker Ivica Olic was ruled out after scans showed that a thigh injury was more serious than initially feared.
Bilic had to call up the 24-year-old Nikola Kalinic, who plays for Ukrainian side Dnepropetrovsk, to replace Olic as his recovery would take between four and six weeks.